Earlier quoted context omitted.
Probably not evil, just incompetent. Many internet multiplayer games today place trust in the client in order to grant a smoother experience on higher latency internet connections, which makes it easier to implement cheating mechanisms. The fight against this is all about verifying the client and the environment it is running in. WINE is quite hackable, so one can see why they'd want to blacklist the platform outrigh…
CSGO (where leagues and MM use third-party anti-cheat) is an example where the community deems the vendor's AC insufficient. The most extreme example is Rockstar Games / GTA V, the multi-billion-dollar revenue AAA title where anyone with a free to download menu has far more power than all Rockstar administrators combined.
The slippery slope of giving companies higher access is also seen in CSGO where (Faceit/ESEA, dont remember who exactly) put a bitcoin miner in their anti-cheat. Capcom put a rootkit into Street Fighter V to check for cheaters. Is that acceptable?