Most effective anticheat in my 25 + years of gaming has been Server admins in Spectator mode, with the ability to ban instantly.
Back in the Medal Of Honor days, there was a fellow named BlackBart with the Invisible Warrior CLAN. He made his own anticheat software.
There were 3 of them : Counter Intelligence, Missionary, Reverend
In order to play on these servers, Each player had to download and run the client . The server side would always be changing at random intervals and the
client side had checks and balances in place that had to match up with the server side. You could not circumvent the system. If you tampered with it, you were banned instantly.
It was an excellent anticheat, and all the best of us in MOHAA and on the OGL ladder played on these servers, either that or we played on other clan servers we knew that always had server admins watching.
BB was able to do it on his own and very little $$$$. He just asked for any donations that people could afford, nothing more.
Electronic Arts net worth as of October 19, 2023 is $34.74B.
Here we have a company worth Billions of dollars that cant come up with a solid anticheat for their games?? I call bull. You have to start asking why cant they ?
Well, they can....they just don't.