This is an absurd comment for two reasons.
Most games aren't multiplayer with anti-cheat requirements. And you're only talking about lazy, client-side anti-cheat systems.
It's impossible to verify everything between eyeball and public network. The drop-in systems available essentially check for known things, good and bad. This war on clients has a front line moving lower and lower into your computer. It used to be process and driver inspection but it's in the process of moving up to UEFI-locked ring0 (Riot's Vanguard) and it'll be a TPM-like hardware module by 2025.
There's another way: INSPECT ACTIONS. Every client knows what's going on, the server —if one exists— knows what's going on. Just replay 10 seconds leading up to a suspicious event and you very quickly discover wall-hacking, or aiming too fast and too accurately, or impossible macros. This system can be automated, cross checked by multiple clients, and you very quickly know if somebody is probably cheating.
Even if you don't want to spend time tuning your machine learning, you can just replay scenarios to other players. Hackers aren't subtle! CSGO's Overwatch is essentially crowdsourced moderation... and it works.
The reason we pretend that client-side checks are the only anti-cheat feature out there is because they're cheap. Drop-in. But they're awful for gamers' freedoms.