It might rather be that 33% of cheaters used (or tricked the game to think that they used) linux to bypass the anti cheat because it was an easy solution (i'm not entirely sure of that statement, I never tried to cheat), not that 33% of the cheaters were cheating because they used linux. There is a slight nuance in my opinion, but I don't really know how to explain it well, I did my best.

Unsupporting Linux just seem to have removed a fairly common way to cheat.

That being said, chances are that cheaters will eventually find other solutions, since anti-cheat is a threadmill work.

But still, that sucks, that was a pretty brutal decision.