I should have said “socially mandatory”. Not mandatory as in you fail your classes if you go walking instead, but it was heavily not ok if your kid doesn’t take part or you can’t buy the equipment for them. My kid was in school just a few years ago still, but it was more rural.
I also did substitute PE teaching for some years and saw a lot of these equipment related financial issues during those times, there was none to give from the school to improve inclusion. Not just with skiis, but with skates and other winter sport stuff as well.
Tbf cross country equipment can be very expensive in a country that is all about cross country skiing.