As well as teach tolerance for other cultures, different perspectives and the humanities in general.

Cancelling tourism across the board will 100% end up with everyone going to war with each other within a single lifetime, by means of the power hungry/money hungry/attention hungry "othering" everything not within eyeshot.

We're essentially talking about de-democratizing cultures and returning power to the hands of the few who get to translate the outside world for us. Idk about you, but I'm not interested in living under INGSOC or a return to cardinals gate-keeping wisdom, and substituting their own, behind the proverbial Latin.

We need to curb greenhouse gases, yes, but we need that by normalizing green tech, not dropping another quarantine curtain on everyone. We need MORE tourism, like it or not. Maybe a state sanctioned, and funded, 2 years before uni for teens to have their own modern 'walkabouts' and get some exposure. We need everyone to gain some culture, after all, the more traveled we are, the less dogmatic and less inclined towards violence we tend to become. Which makes governing a population have to focus more on coercion and policy/dialectics and perhaps there's the rub. It's easier to start programming the young (kindergarten) with nationalism than sway opinions with rationality. Maybe that's where the burnt of modern problems stem from.