Cheating is a big draw to Windows for semi-pro gamers and mid streamers. What else is there to do except grind? Windows gives the illusion of "kernel level anti-cheat," which filters out the simplest ones, and fools most people some of the time.
For instance, a common cheat in Street Fighter 6 is to trigger a drive impact in response to the startup of a move that is unsafe to a drive impact. That is recognizing the opponent's animation and triggering an input. There's no part of that which cares where the game simulation is being done. In fact, this kind of cheating can only be detected statistically. And the cheats have tools to combat that by adding random triggering chances and delays. It's pretty easy to tune a cheat to be approximately as effective as a high-level player.
Kernel-level anticheat isn't a perfect solution, but there are people asking for it. It would make cheating a lot harder, at least.
As does Valorant and virtually every other first person shooter. The cheats aren't people flying around or nocliping, it's wallhacks and aim assists/bots.
I can move and reveal what's behind a corner a lot faster than a network roundtrip, so either the server needs to give some advance warning or you're going to see enemies pop into existence suddenly.
And computing if somebody is almost visible isn't trivial either. Level geometry can have narrow openings such as holes in a wall. Or what if somebody jumps?
And that's before getting into non visual information. It's not perfect, but you could still add a significant advantage by drawing the exact location of footsteps.
So yeah, (some) games try, but network latency means the client needs some information a wallhack can use, and the alternative: being killed by an enemy that was invisible is at least as frustrating as being killed by a cheater so the visibility estimate has to be generous.