Developers have full control over servers in most cases. A viable server side anti cheat should be a thing. For every case of "client sending false data to server" we can come up with a solution to verify that to some degree. Finally, it should help a lot to rely on player generated reports and utilize replay recording on server.

But no, developers will continue to rely on 3rd party solutions (made by people who never developed a game), even infect their co-op-only games with it, and complain "uh oh we can't handle Linux cheaters".