>Nobody is going to reasonably suffer

Your definition of reasonable is not universal. For many people, life is for living, not for sacrificing worldly pleasures to eke out as long an existence as possible.

This isn't about sacrificing all worldly pleasures or even all vacations.

It's about perhaps rethinking whether one needs to fly so often for one's vacations.

A lot of people don't live on the same continent that they were born on and vacations are the only time they get to see their families.

I already know some who did suffer (perhaps unreasonably but that's in the end irrelevant).

Perhaps "suffer" isn't great here, because it's used coloquially as "being affected" and to literally suffer because of something. People will be affected, absolutely. And some people might also suffer from not being able to have an international vacation. But probably not reasonably so, i.e. a reasonable person would not suffer in that situation. You can suffer unreasonably, and you're right, it's irrelevant to the question of "does suffering exist", but it's very relevant to the question of "should we do something about it as society". If it's reasonable, probably. Otherwise that's between an individual and their therapist.