The term "league of choice" is one that is often bandied about by Major League Soccer executives. The intention is to portray MLS as a league on the upswing, in a way that is starkly different than the labels often foisted upon it.

"Retirement league" is the moniker that is the most cutting, the implication being that it's a place where aging stars go to earn fat paychecks against substandard competition when the rigors of more competitive leagues become too great.

It's a cheap, easy label to lob at a league containing more than 600 players, yet there have been times when there was some truth attached to it. The likes of Frank Lampard, Andrea Pirlo and Steven Gerrard arrived and made little impact in terms of on-field contribution. Even when a Thierry Henry or a Didier Drogba excelled, that was used as a criticism that such aging stars could still dominate at times.

That said, the reality, one that has accelerated in recent years, has seen a greater emphasis on younger players. While older stars like Bastian Schweinsteiger occasionally make their way to North America, younger performers like Atlanta United's Ezequiel Barco and New York City FC's Jesus Medina have become more prevalent, as have still-in-their-prime players like LAFC's Carlos Vela and the Seattle Sounders' Nicolas Lodeiro.

According to the Elias Sports Bureau, the average age of players starting on opening day last season was 28.0 years. MLS stated that of the 91 players signed by its clubs this offseason from outside the league, the average age is 24.9.

So how then, should MLS be viewed beyond the "league of choice" mantra? Is it a feeder league for players on the rise? Is it a developer -- and hoarder -- of domestic talent? Is it simply a league aspiring to put the best product on the field, all while appealing to a diverse audience, regardless of the consequences to the U.S. and Canadian men's national teams? Only that last question can be answered in the affirmative.

Is MLS a feeder league?

MLS has long shunned the feeder-league label over concerns that the optics of selling its most talented players to foreign clubs would give the appearances of diminishing quality. Sure, there have been occasions when MLS has transferred some of its better-known players -- be it Obafemi Martins to Shanghai Shenhua or Jack Harrison to Manchester City -- but the norm is to let contracts wind down and either re-sign the player or watch him leave for other leagues for free, as was the case with U.S. U-20 standout Erik Palmer-Brown.

But at some point this reluctance to sell will need to change. A player like Atlanta's Miguel Almiron didn't come to MLS to finish his career here, but to use it as a means of moving on to bigger stages. If MLS continues to hold onto players until the end of their contracts, it may find recruiting such players to be more difficult, diminishing the "league of choice" mantra it espouses. At least outwardly, this is a development recognized by those at MLS headquarters.

"For sure I think there will be some additional pressure or increased appetite and interest in our players because they're obviously of a higher quality than we've previously had," said MLS senior vice president for competition and player relations Lino DiCuollo. "I think for sure as this process continues, or accelerates, we will be similar to other countries where elite players will not only be coming in but we'll be transferring some of them out to other teams and using the transfer fees to finance the next acquisition."

U.S. international Tyler Adams, 20, is blossoming at a time when opportunities in MLS are increasingly being given to foreign players. Mike DiNovo-USA TODAY Sport

Is MLS a developer of domestic talent?

In terms of developing domestic talent, it appears as though this is becoming less of a priority for MLS. The league constantly touts the investment teams makes in their academies, and that is all well and good, especially when a player like the New York Red Bulls' Tyler Adams breaks through. Numbers provided by MLS have seen minutes for homegrown players balloon to more than 74,000 last season as the league's academies have matured.

But looking at the league as a whole, it's clear that foreign players are taking up more and more of the available playing time. According to the Elias Sports Bureau, the percentage of minutes for U.S.-born players has fallen from 52.7 percent in 2013 to 42.2 percent last season. The numbers drop further when the number looks only at players eligible to play for the U.S., which includes a naturalized citizen like Darlington Nagbe, but not Steven Beitashour, who represents Iran. Numbers compiled by ESPN FC show that in 2017 that number shrunk to 37.7 percent from around 52 percent in 2012.

By point of comparison, a study by the International Centre for Sports Studies' (CIES) Football Observatory found that halfway through the 2017-18 campaign, domestic players accounted for 38.8 percent of the minutes in the Premier League and 50.5 percent of playing time in the Bundesliga.

The disparity is even more pronounced in terms of what positions domestic players are occupying. Looking at the projected opening-day starting lineups for this season's 23 teams, 93 U.S.-eligible players should see the field, but only 27 of those could be considered attacking players.

In light of the U.S. national team's failure to qualify for the 2018 World Cup, the topic of playing time for domestic players is one that has been raised with more frequency, but DiCuollo insists that opportunities for domestic players are still there.

"At this time, there are still many domestic players playing and contributing," he said. "We did look at it and I don't think we saw any noticeable decline by the domestic players. "We're continuing to try to improve the overall quality on the field in a number of ways, and we don't feel that there is this letdown on the domestic player part. The ones that are good will continue to get good deals and continue to play more whether they are younger, midlevel or older age range. As of right now, we're not seeing that [letdown]."

There are two primary reasons for the foreign influx. The introduction of Targeted Allocation Money (TAM) has pumped considerably more funds into the system in recent years -- it currently stands at $2.8 million of discretionary and $1.2 million of non-discretionary -- that have served to buy down the salaries of a select group of players making between $500,000 and $1 million a year. These come mostly from abroad. DiCuollo insists that doesn't mean domestics can't venture into TAM territory.

"The question isn't 'Is he TAM?' but what is his value determined by contract length, his age, his other opportunities, his value to the league?" he said. "You look at a host of those factors. With our experience, you look at it. Sometimes the teams will come to us and say this is what we think, and if there is a discrepancy with what we think, we will speak with a number of other teams and sources that we feel can contribute value in this area in terms of their opinion, and you come to a decision."

But the league's single-entity structure, whereby it is the final arbiter of what a player can earn, is also a factor in making life more difficult for domestic players. The single-entity system creates a layer of insulation from the international market considering in almost every case, MLS teams are forbidden from bidding against each other for a player's services.

It's not until a player leaves MLS that he is fully exposed to the effects of supply and demand. As an example, New England Revolution forward Juan Agudelo made $175,000 in guaranteed compensation in 2013 prior to signing with Stoke City, but saw that figure jump to $427,000 when he returned to MLS in 2015, despite very little demonstrative growth during his brief stint in Europe.

The speed with which foreign players are able to collect green cards, and thus count as domestic players, has been a factor as well, allowing teams to circumvent the number of international roster spots (usually eight) that it holds. Atlanta United's Tito Villalba recently acquired a green card a little more than a year after arriving, as did the San Jose Earthquakes' Florian Jungwirth.

These actions have served to dampen the league's claim of how important it is to develop domestic players.

Is MLS simply a league aspiring to put the best product on the field?

To be clear, MLS is in the entertainment business, and its primary and perhaps only obligation is to make the level of play as high as it can. This has been a challenge in the face of an expansion boom that has seen the league more than double in size since 2004. MLS has long stated that the quality of play wouldn't be diluted given its access to the international market. The best way to combat this is to bring in more players from abroad. In a sport with a multi-cultural fan base, MLS has rightly sought to highlight the diversity of its player pool, one that has seen performers from 34 different countries sign with the league this past offseason.

There is also something to be said for forcing domestic talents to compete against a higher caliber of import. A U.S. or Canadian player that breaks through will have scaled a higher bar in order to get playing time, which ought to benefit them both at league and international level.

But MLS can't be all things to all people. Being a feeder league seems at odds with accumulating talent. The same goes for when the quality of play is set against developing domestic players. DiCuollo insists that MLS will try to strike a balance.

"If you look at the top five to 10 leagues in the world, they all have elite young players, good domestic players, very good older players and they all have robust transfer markets," he said. "They have players coming in and if the player does well, they're moving on for significant transfer revenue. I think that's all part of the process for a league to grow and to reach the elite leagues in the world, and I think we're going through the same growing pains."

So as MLS enters its 23rd season, the "league of choice" moniker lives on, it's just that some players have significantly better choices than others.