My understanding is that they are much less generous on average compared to U.S.

E.g. for now I have the most premium card offered by my bank (50€/mo), and it gets me extra product insurance, rental car insurance, travel insurance, free lounge access, and some other things like that, but no cashback or similar.

I think some premium cards do offer cashback nowadays, but they are in the minority. Some cards also offer airline reward points. My experience is limited to Finland, though.