I'm someone who hasn't used Windows for gaming in years, and has been enjoying Proton since 2019.
But, especially for children, a lot of these games are a big part of their social lives. Paragraphs could be expended on the vices of these games, but I disagree with considering them easily ignored.
As others have noted though, a surprising lot of these games with anticheat do work on Linux. It's not even rareOverwatch, Halo, and Helldivers to name a few.
Plenty of games without anticheat won't work either. It's far from the Windows situation of installing whatever you want and expecting it to work out of the box. And the "gold" rating on ProtonDB/WineHQ means nothing, you have to check the comments.
Sure Linux also works with a lot of games nowadays, and you can ignore whatever doesn't. I use a Mac and accept that it'll run even fewer games. Not my priority.
We're entering a world where developers are going to need to start implementing anti cheat that works on Linux. It's clearly possible, and as we break past 5% it's no longer economically viable to ignore Linux. Especially once the GabeCube comes out...
The goal of kernel mode anticheat is to prevent other kernel-mode modules from tampering with the game's memory. This can kind of be done on Windows, as there's a pretty short list of kernel binaries, and all device drivers are signed.
This is out of the question on Linux, where there's probably 100,000 distro kernel binaries floating around, plus the ability to build your own with whatever modules you wish.
The only plausible solution is to force everyone to use the same kernel image. "To run Valorant, please apt install linux-vanguard-botnet-bin!"
Unfortunately this is a plausable enough outcome, and those games are so absurdly popular, that people will do it, especially given that having support for these games will likely drive new users to Linux.
If enough people do it, this opens the door for other software to latch onto it and start requiring a "verified kernel", so I'd rather just never see these games on Linux.
I think, it's not unreasonable to see basically a verifiable reference single-purpose gaming OS everyone has to use in competitive esports games. Steam and Linux are probably positioned well there.
Would be hilarious, if all gaming ultimately settles on a hardware independent console platform running on a locked-down linux! This would really please and piss off every faction at the same time. But honestly, not the worst compromise IMO.
We probably could run Linux distros under hypervisor (just like default Windows install those days runs not on bare metal, but under Hyper-V).
And then games that wish for anticheat start a separate VM in hypervisor with complete secure boot chain of trust. Would require GPUs to support SR-IOV though.
Maybe something using AI could be implemented - does a screenshot of your game e.g. every second and if it detects anything that would suggest cheating then it informs some central system and sends it a movie of you playing for the final verdict.
Of course this all is based on the assumption that the local AI can do this fast enough with enough precision.
I wish you were right, though