Yes, the only reason I keep a windows install around at all is for MW2, Tarkov and Hunt: Showdown with the boys.
From memory, Valve has also been supporting anti-cheat providers to port to Linux (or perhaps I have misunderstood and they will also run under Proton?), so there’s always a chance this will be solved in the next couple of years. The Steam Deck has been a great catalyst for that within Valve, it seems.
I think some publishers are reluctant because on Windows, those anti-cheat systems involve out-and-out rootkits, so allowing Proton support for them is seen as a relaxation of their 'security'— the Linux ports of those systems are userspace only, Proton and Wine don't have that kind of kernel access anyway, etc.
I think if, over time, it looks like those fears are unfounded and there are few practical problems with anti-cheat for competitive games on Linux, then probably some currently-hesitant publishers will relent and enable their games on Linux. But only time will tell, I suppose.
From memory, Valve has also been supporting anti-cheat providers to port to Linux (or perhaps I have misunderstood and they will also run under Proton?), so there’s always a chance this will be solved in the next couple of years. The Steam Deck has been a great catalyst for that within Valve, it seems.