Valve have been doing it with Counter Strike for at least 3 years. And the "VACnet" they have is still far from perfect. Especially with the less obvious cheats. They used to be a talk on youtube, but it seems to have been taken down.
I did a few hundred cs overwatch (it's a system where people with 150+ won matches can review suspicious behaviours reported by system/other users - https://blog.counter-strike.net/index.php/overwatch/) cases and 95% of them were people using Spinbots. You can write a program/script that parses demos and detects those in few hours (assuming you don't know how to parse a demo file). Why is this even a thing? I want to help them with fighting less than obvious cheaters but if almost everything I get can be automated by any 1st-year cs college student then what is the point?
