Is the pollution and co2 production worth it so more people can take photos in front of things? Maybe it is, maybe it isnt.

Or also for the "middle" class but as an expensive treat that would have been chosen over something else, like it used to be. After all the environmental cost of a 20€ EasyJet ticket isn't nothing.

Well, problem here is that airlines are under control of national regulatory agencies while flying internationally. Sure, a mandate of say, drastically improving comfort levels by making something like an old-style business class seat (38" pitch recliner, 4 abreast in a narrowbody) the absolute allowed minimum - could work: it will make passengers happier, reduce air rage, and lift prices to the level that somewhat curbs overtourism. But it's impossible to introduce because if one nation does so it will simply make their airlines uncompetitive abroad.

How far do you want to take that? The oligarchs can fly back and forth to Japan every week, should the air fare be so cheap that everyone can do that?

That’s a fair counter point, but I’m just saying that it did have negative consequences and we might want to consider it. It’s kinda crazy you can sometimes fly 6000 km for less than a few round trip train tickets between London and Edinburgh.

I wonder if Americans’ pitifully short vacation allowance paired with high incomes is an issue. If you’re going to Japan for a week you’re likely to only hit a few top attractions, I imagine.