You're thinking of a virtually impossible situation, that is, people living in abject poverty in all ways but they take a plane flight once a decade, this isn't how things work. The people that travel by plane use far more resources than these poor people.

Complete contradiction of the previous points you made. /u/ywain literally made a point that the rich abuse travel, and that if they didn't then more non-rich people could travel.

The people that travel by plane use far more resources than these poor people.

Yes, this was pointed out already.

It's almost certainly far less ecologically damaging for an already wealthy person that can afford a plane flight to add an additional flight, than the damage of bringing a poor person into a class that could afford plane travel for the purpose of becoming more cultured.

What? Either you have no idea what you're trying to say, or it's one of the most poorly worded arguments I've read.

The poor people I'm talking about have serious food insecurity and often live in war torn areas or in the middle of civil wars, they're not interested in becoming enlightened.

True, but that was not the point of the original discussion. You're moving goal posts now.

A 9x reduction of our current levels still leads to ecological collapse, it just takes a few decades longer.

Commercial passenger flights don't account for all that much. Aviation as a whole accounts for about 2% of global greenhouse emissions. Not insignificant, but not at all the biggest. The vast majority comes from dirty power generation (coal, gas, etc).

You gotta think about much more than the plane flights themselves, think about everything it takes to enable plane travel, the resource extraction needed to design, build, and maintain planes and airports, etc.

The planes and infrastructure already exists. There's about 5 billion flights each year. And the prolific fliers make up a disproportionate number of those fights.

Plane travel doesn't exist in a vacuum, it's an artifact of a fundamentally unsustainable way of life.

This isn't true at all. Not even in the slightest.

If all the poor people started flying, would those who fly multiple times reduce their travel to make up for it?

You mean in our completely hypothetical and 100% chance of never happening scenario of all the poor people suddenly flying regularly? Then yes, the frequent fliers would reduce their travel.

Most plane travel is for enlightening people about other cultures, it's for business, or for visiting distant tourist traps, not worth the damage or exclusivity.

Well, you kinda just highlighted your Americanism just now. It's mostly Americans who have the need to travel to other counties for dentist work. People in other countries either don't have to, because of real healthcare, or just don't get dental work because they live in countries of poverty.

It would go from 2% to 4% of greenhouse gas emissions. Objectively not a good thing, but not "devastating". There are many other things that are taking care of that just fine (like China's absurd amount of coal plants).

So encouraging travel as if it's an inherently good thing we should all aspire too is incredibly destructive

Not at all, because air travel is not the source of, or cause of, our climate disaster. Power generation is main and biggest issue. And countries like the US and China hold the brunt of onus for it. Nearly every other country is doing amazingly with clean energy generation. Most of Canada's provinces are above 95% clean energy. Ontario is at 80+% and rapidly improving that number. With Alberta being the issue for burning gas. But overall the country is at about 75% clean energy (maybe higher, came remember the exact number).

The US is barely hitting 40%, and China is worse.