I would say it’s valid enough if there going against 1,500s, chess.com will not change that.
Options on other chess sites

Honestly neither of them are going to be to accurate fide-wise, super gms are 3300+ on chess.com but only 2800ish for fide, im pretty sure super gms can get to like, 3500 though on lichess?
I have friends who play on lichess and even chesskid but if someone was a 1500 on lichess would you consider them 1500 or do you consider chess.com to be most accurate?