Maybe
Guess how many GM is in Chess.com
There are probably around 1500 GMs in the world right now. I'd say only about a third of them would use chess.com, so my official answer is 500 chess.com users are FIDE grandmasters.
https://www.chess.com/members/titled-players/grandmasters?&page=48
There are 48 pages, so there are 47*25+22=1222 GMs, though many are inactive.
1300, about
I say about 2000
Pretty sure the active number of GMs is less than that and is closer to 1500.