D UBAI IS OFTEN called a “Disneyland for the rich”. At the city’s airport the three first-class lounges of Emirates, the United Arab Emirates’ flag-carrier, do not disappoint. Each one is as big as the terminal’s concourse, built to accommodate thousands of passengers. But every day only a hundred or so enter each first-class lounge. Instead of the overpriced fast-food on offer in the public concourse, a maze of restaurants and bars serve free caviar and champagne. In their duty-free sections no knock-off cigarettes or booze are in sight. Think instead Bulgari necklaces and whisky at $25,000 a bottle. The facility is so large, its manager admits, that the most common reaction heard from new arrivals is, “Oh my God, where is the lounge?”

Yet the rows of hundreds of empty armchairs suggest that something is not quite right. Airlines are falling out of love with first class. And that is true even of Emirates, which sells far more first-class tickets than any other carrier (see chart 1). The time to launch new first-class offerings is at ITB Berlin, the world’s largest trade show for the travel industry, which opened on March 6th. At this event in 2017 Emirates unveiled a new onboard bar and lounge for its highest-paying passengers. The same year its big rival in the Gulf, Qatar Airways, launched the world’s first skyborne double-beds. But the mood has changed. Last year Emirates stopped attending the show at all.

The decline of first-class air travel seems at first glance surprising. Facilities onboard have never been so good. On its A 380 superjumbos, Emirates first class provides in-flight showers. Moreover, the number of very rich people has risen sharply. Forbes, a magazine, estimates that the stock of billionaires has doubled to more than 2,100 over the past two decades. And the rest of the luxury-travel business is booming. Richard Clarke of Bernstein, a research firm, estimates that the number of luxury hotels in Asia could increase by as much as 168% over the next decade.

Even so, many analysts predict that first class will soon disappear. In America it is already almost extinct. Ten or so years ago almost all the many hundreds of long-haul aircraft based there offered first-class seating; now only about 20 do. Elsewhere in the world an increasing number of airlines, including Turkish Airlines and Air New Zealand, have already scrapped it completely. On the majority of the most-travelled long-haul routes the number of first-class seats available has fallen sharply in the past decade (see chart 2). Even the airlines that sell the most first-class fares are curbing their enthusiasm. The number of first-class seats has been slashed from 14 to 11 on Emirates’ superjumbos and from 12 to six on those flown by Singapore Airlines.

When commercial aviation got going after the second world war there was only one class: first. Economy appeared in the 1950s. It was followed in the 1970s by business class and in the 1990s by premium economy, to fill the gap between business and cattle class. Despite the proliferation of cheaper seats, airlines still make a lot of their money from the more expensive ones. Emirates claims that first- and business-class passengers are 12% of the total but generate about 40% of its turnover. High demand for flat beds on transatlantic flights is what has saved European flag-carriers such as British Airways (BA) , Air France and Lufthansa from going out of business. Ross Harvey of Davy, a stockbroker, points out that transatlantic low-cost airlines that have tried to offer just economy or premium-economy seats, such as Norwegian and WOW , have struggled to make money. Airline bosses are acutely worried about the decline in demand for first class. But they have themselves partly to blame. The industry has disrupted itself, points out Geoffrey Weston of Bain & Company, a consultancy. On short-haul flights, the low-cost model has won. Most “first-class” passengers on these routes now sit in seats with the same legroom as economy passengers, albeit with an empty middle seat, and make do with extras such as lounge access, and food and drink. On longer routes, new seats that turned into fully flat beds were a game-changer. These were originally introduced by BA in first class in 1995, and much sought after. If travellers can sleep comfortably in the sky, they can save the cost of a hotel or, more importantly for time-pressed corporate warriors, a day’s working time. However, in 2000 BA launched a similar seat in business, and most carriers have followed suit. That has weakened the case for flying first class. Most companies think a flat bed in business class is good enough for their employees. Only a few honchos are allowed to enjoy first class on the company dime, says Greeley Koch of the Association of Corporate Travel Executives, a trade group.

Changing attitudes among the very rich are also sapping demand. Over the past decade the number of billionaires has grown fastest in China, India and the tech hubs of America. But many self-made tycoons want their children to have the “normal” middle-class upbringings they themselves had, says Charlotte Vangsgaard of R e D Associates, a consultancy. So they book themselves and their families into business, or sometimes economy, rather than first.

Airlines that offer first class say they still do so for two main reasons. The first is to use upgrades from business class as an incentive for loyalty from both corporate and individual customers. But as the gap between business and first has narrowed, frequent flyers have begun to respond better to other incentives, such as access to lounges or to special hotlines.

The second reason for maintaining first class is also weakening. That is what Samuel Engel of ICF , another consultancy, calls the “halo effect” an airline creates by advertising first-class facilities. In other words, flyers begin to think economy on Emirates, say, is fancier than on other airlines by association with features in its first class, such as in-flight showers. This can be an effective marketing tool. For instance, Etihad, a rival to Emirates in the Gulf, has probably had more press coverage for its onboard first-class apartments called “The Residence”, of which it has only ten, than all its 30,000 other seats combined.

Many airlines, however, are no longer convinced by this argument and have slimmed down their first-class offerings. One such is Air France- KLM, whose chief executive in 2014, Alexandre de Juniac, claimed that first class was “little more than a costly marketing gimmick” and that “no one makes money out of it”.

Yet some still do, particularly Emirates. One advantage it has is that it can combine traffic from various destinations using its hub in Dubai. This helps it make first class viable on routes where it might otherwise struggle to attract first-class passengers. As a result, over 90% of its first-class bookings are paid for, rather than free upgrades.

Why do some passengers still want to fly first rather than business? Privacy is one reason, says Sir Tim Clark, the airline’s president. Smaller cabins and walled-off seats make it easier for a celebrity to fly unnoticed by fellow passengers who might otherwise tweet unflattering pictures of them drooling in their sleep. Another is flexibility. First-class passengers want to sleep and eat when they choose, not on a timetable set by cabin crew, as often happens in business class, says Joost Heymeijer, head of Emirates Inflight Catering.

But even Emirates’ first- and business-class sales are threatened by private jets. These let executives avoid the wait for a scheduled flight. It is also much quicker to pass through security in a private-jet terminal than an airport. And in America ten times as many airports are open to private jets as are available for the bigger aircraft airlines use. Moreover, executive jets are becoming cheaper in relative terms, says Adam Twidell of PrivateFly, a private-jet booking service. New shared-ownership and ride-hailing services allow the cost of a private jet to be spread over many users.

The rise of the private jet may be good news for bigwigs rushing to meetings. But it is bad news for the environment. The World Bank estimates that first- and business-class passengers on a narrow-body jet already generate between 2.5 and six times more carbon emissions per person than the poor saps crammed into the cheap seats. Private jets, obviously, are worse. A half-filled private jet is roughly five times dirtier than business class and 12 times dirtier than economy on short-haul routes.

A new breed of supersonic executive jets will be even more polluting. The International Council on Clean Transportation, a think-tank, estimates that their emissions will be five to seven times greater than for standard jets. Boom, one of the startups hoping to produce these jets, has forecast that up to 2,000 such supersonic aircraft will be built by 2035.

Another trend that could hasten the end of the arms race in first-class facilities is the shift towards smaller passenger jets. On February 14th Airbus, maker of the A 380 superjumbo, announced that it will stop production of new ones from 2021. This aircraft’s bulbous fuselage left space that could be devoted to fancy first-class features such as Emirates’ showers and Etihad’s apartment suites. The smaller and more efficient jets that have consigned the A 380 to an early grave lack this extra space. It would be hard to fit showers, for instance, in the new long-haul narrow-body jets now available.

So Emirates will need another way to get its passengers to pay extra—perhaps by further upgrading those cavernous lounges. Its lounge manager in Dubai sounds perplexed: “You need to do something different to make first class worth it.”