T-Mobile says it’ll launch a 5G home internet service with fast speeds, easy installation, and low prices that will reach half of all US homes within five years and meaningfully shake up the woefully anti-competitive cable industry. There’s just one catch: T-Mobile says this only comes true if its Sprint merger is approved.

In a blog post and Federal Communications Commission filing today, T-Mobile outlines in the most detail yet what its 5G home internet service will look like. The company started divulging some details around the offering last September, but with today’s CEO-written blog post, T-Mobile is starting to advertise its promises in a far more public fashion.

T-Mobile says it plans to create a true cable competitor using 5G, offering speeds at 100 Mbps or higher. It’ll come at an unspecified lower cost, and customers will be able to set up the system themselves, so they won’t have to wait around for someone to install it. T-Mobile thinks it can have 9.5 million customers within five years, and save customers up to $13 billion in that time because of the increased competition.

It’s about shifting the conversation from wireless competition to wired

It’s an exciting picture, but the thing to remember is that this is all a big, beautiful dream that T-Mobile is describing to get its merger approved.

If T-Mobile and Sprint merge, the United States would shrink from four major wireless carriers down to three. The previous leader of the FCC repeatedly said that four carriers are necessary to maintain a competitive environment. And while the current leader doesn’t seem to believe that, this general concern is a big element of what’s holding up the 10-month-old merger agreement.

Making the argument that the wireless industry will be more competitive with one fewer competitor is hard (T-Mobile has, of course, made it anyway). So instead, T-Mobile is trying to make it appear that the merger will dramatically increase competition in another industry: home internet.

It’s not the worst argument. The cable industry is pretty much just monopoly after monopoly. Nearly half of all households lack a second option for wired broadband service, if they even have one option in the first place. Because these 5G networks would be substantially wireless, companies like T-Mobile might be able to quickly move into areas that cable companies have long avoided due to the challenges and expenses around laying cables.

T-Mobile isn’t the only company planning at-home 5G internet

The current FCC has even indicated that it views wireless as an alternative for wired broadband since it can have comparable speeds. That isn’t at all how it works in reality — wireless speeds are still slower on the whole and way more expensive — but T-Mobile describes a future where that isn’t the case and wireless truly is a legitimate alternative to wired internet.

It’s an argument that regulators are eager to hear. The question is: is the Sprint merger really necessary for all of this to happen? AT&T and Verizon are investing in many of the same 5G technologies that T-Mobile is. Verizon has even launched a pilot 5G home internet service already. So it’s not as though T-Mobile is the only company that’s capable of doing this.

T-Mobile mentions using Sprint’s airwaves to deliver this service, which helps to bolster its argument that the merger is necessary for its own deployment. But it’s not clear whether those airwaves are truly critical. In its FCC filing, T-Mobile says the deployment “produces a very large increment to capacity all at once” and that “much of it available to provide wireless fixed broadband service.” But that’s combined with other airwaves T-Mobile already owns.

To get things started, T-Mobile says it’ll “soon” begin testing a wireless home internet service using its LTE network. After the merger, T-Mobile says, it’ll be upgraded to include 5G.

The plans almost echo what’s happening at Verizon, which has paused its 5G home internet deployment plans until later this year. These companies are clearly eager to get the most out of their 5G investments. But for now, the shift into home internet delivery is still just a pitch that no one’s really moving on.