I think it's more that air conditioning is (currently) prohibitively expensive. The few people I know that have it spent several thousands of euros on their installations. That's not something most people have lying around.
You'd think the government could subsidize aircon like they did solar for years, and both of those things combined would translate to very pleasant summers spent in energy neutral air conditioned homes.
A basic window AC unit costs a few hundred bucks.
You don't even need an expensive AC. If you can't afford one, you can just get an evaporative cooler[1] for $100 or lesser[2]. Possibly even cheaper if you don't mind buying a second-hand unit.
You don't need to get central A/C or mini splits. You can use an efficient Window unit (not those single ducted portable units that are just barely better than nothing. if portable do dual ducted for efficiency) Those window units are available at Walmart in the US for a couple hundred apiece. Presumably hypermarts like Carrefour would carry them or some places that serve home improvement.
It's strange what people think is expensive. Double glazing is very expensive but no one in Europe would go without it. Aircon is not expensive within the context of a house's construction costs.