I don't have AC at home. Some think I don't install it because I somehow don't get hot in summer or cold at winter. It's the other way around. We, people, have one of the best thermoregulation systems among animals, our whole skin is essentially a huge cooling system. The only way to render it incapable is... stop using it for a prolonged amount of time. It's use it or lose it all over again.
If you don't believe me, read what ultra-marathon runners have to say. If a trained athlete can survive Badwater, almost everyone can train themselves to survive a European heatwave.
Sure, some people can't. Some need AC because of cardiovascular conditions. It's fine, let them have it. But some people can't walk because of musculoskeletal conditions, but no one would argue that a wheelchair is a necessity.