Anti cheats are as much a marketing ploy as they're actual anti cheats. People believe everyone is cheating so it must be true. People believe nobody bypasses the FACEIT anti cheat so it must be true. Neither of those are correct.
Riot revels in this by marketing their anti cheat, but there are always going to be cheaters. And sooner or later we will have vulnerabilities in their kernel spyware. I much rather face a few cheaters here and there (which is not as common as people make it to be on high trust factor).
You think tournament organizers or pro players know the first thing about anti cheats? They buy the marketing just like everybody else.