FACEIT is yet another completely useless, doesn't-actually-work, trust-the-client anti-cheating tool. Basically, it makes it so that cheaters (and the game publisher) can claim cheating isn't happening because, "there's an anti-cheat tool" but in reality it doesn't stop actual cheaters.

The entire purpose of anti-cheat tools appears to be to stop casual Linux gamers from being able to play the game. Microsoft has a big part in it as well because the very same intentional vulnerabilities in Windows that hackers use to install undetectable rootkits are what get used by anti-cheat software.

If Microsoft wanted they could close those vulnerabilities by making all privilege levels above administrator (of which Windows has two which is insane) inaccessible to anyone but Microsoft. Instead they just collect money from 3rd party vendors to sign their driver encryption keys, inherently trusting those vendors not to make software with vulnerabilities. It's a recipe for insecurity and Microsoft likes it that way. It acts as a form of vendor lock-in.

Anti-cheat tools pretty much all work with the same basic assumption: Trust the client. What's the first rule of network programming? Never trust the client!