I've been skiing Squaw since 1978 and...
Yep, the movie is a bad directing/scriptwriting/acting joke but I've been around.
Although I was never successful at it I do recall the early-80's, pre-HIV and pre-MADD apres-ski scene WAS pretty raunchy. I haven't heard of a wet T-Shirt contest in Tahoe in years, however.
The thing that really dates the movie isn't the outfits, it's that they're doing *turns* to get down the mountain. With today's skis/snowboards you just go straight down the hill.