Long before the era of Ryanair charges, those who flew knew the importance of minimising baggage. According to the French pilot and author Antoine de Saint-Exupéry: “He who would travel happily must travel light.”

But now, even a case small enough to fit an aircraft’s overhead locker does not guarantee a passenger’s happiness.

From November, Ryanair will only permit cases in the cabin for those who pay a £6 priority boarding fee. Other passengers will now have to pay £8 online to check a small wheeled case into the hold. Just one small bag, to fit under the seat in front, will be freely permitted.

Coming from an airline that has failed to shake a reputation for giving nothing away, the new rules have provoked angry reaction online and accusations of cynical profiteering. Ryanair, however, insists the aim is to cut delays caused by passengers scrambling to stow luggage, which have kept planes on the tarmac too long for tight airline schedules.

While checked-in baggage revenues have been an important stream of income, the Irish airline has already cut the high fees it once espoused. The changes, it says, will not make money: indeed, the new £8 price for a sub-10kg checked-in suitcase may encourage some to pack lighter and avoid fees of £25 or more to put a heavier case in the hold.

Aviation experts are inclined to agree. John Strickland says: “It could be a revenue opportunity – but Ryanair’s average fare is €40 [£36] and average ancillary revenue per passenger is €12. They still have to fill those planes, and to succeed in flying 130 million people a year, they have stick to that mantra of affordable travel, whether it is the ticket price or the add-ons customers are obliged to pay.”

Edmond Rose, an aviation consultant whose past jobs include director of revenue at Virgin Atlantic, says: “There’s no doubt that when you’re charging for checked baggage it is a money raiser – because the cost of handling is an awful lot less than the prices airlines charge.

“But Ryanair’s isn’t particularly high, and the fact they’ve limited numbers [of passengers who can book priority seats] does show that the real problem is the overhead bins.”

Overhead locker space has failed to match demand. Planes are departing ever fuller, typically now with more than 90% of seats sold on every flight, as the airline industry keeps an even tighter focus on costs.

And passengers have adapted their habits to match. They were encouraged to bring bags into the cabin when airlines separated out checked luggage charges in order to advertise rock-bottom headline fares.

Budget airlines have spread across the world in a symbiotic relationship with the small wheeled case, whose widespread use is often dated back to the Rollaboard, invented by a pilot in 1987, in a modern aviation culture of short breaks and minimal costs.

And passengers have turned the tables on the bean-counters to the point where Ryanair’s finance director last year bemoaned the sight of toddlers with wheelies, the result of passengers who weren’t “playing by the rules” and “taking the piss”.

However galling that sight may have been, the bigger factor ultimately appears to be the wheelie’s threat to turnaround times of as brief as 25 minutes between flights, which are central to budget airline economics.

“There’s a bit of money in it, but punctuality and quick boarding is more important, not having passengers blocking everyone else while they wrestle to make a bit of space in the overhead,” says Rose. “What’s interesting with cabin baggage is that airlines keep trying different ways to allow it or charge for it – it keeps swinging around.”

The Hungarian airline Wizz initially charged for all cabin bags, before abandoning the policy last year. British Airways and Virgin have marketed some fares for hand-luggage only, rather than appear to charge extra for checking bags, but both have generous carry-on allowances. Ryanair is now abandoning a recent rule change that allowed wheeled cases to be taken at the gate and put in the aircraft hold for free.

A spokesman for London Stansted airport, Ryanair’s biggest UK base, said summer shifts on the frontline had shown that something had to change. “The policy of putting cases in the hold at the boarding gate was a false economy, in terms of the efforts involved at the gate and the impact it was having on flight delays.”

The baggage picture is further complicated by Ryanair’s own contracts with airports: it relaxed its more stringent clampdowns on carry-ons in 2013 to get preferential terms at Stansted, promising more passengers shopping in airport shops. Although the airline doesn’t spell it out for passengers, it will still allow those duty-free shopping bags on board as well.

Last year, rival easyJet lowered charges significantly for smaller checked-in bags, weighing under 15kg. It also launched a “hands free” service, designed to encourage passengers already at the airport to check in small cases, rather than drag them through security and on to the plane, for a £5 fee. From a different angle, with typical controversy, Ryanair may well have ended up in a similar place.