It's so much easier to make cheats today than it was, say, 10 years ago.
It's also easier because more and more games are sharing common infrastructure like game engines, as compared to the past. What works in one Unreal game may save you a lot of time developing a cheat for another Unreal game.
These days, many online games encounter serious cheats within the first couple of days of release - if not the day OF release.
Cheating and anti-cheat used to rely a lot on the pure technical parts (like "is something sneaking some reads from the memory the game engine uses to clip models?"), which is ultimately not something you will win as a game developer (DMA/Hardware attacks or even just frame grabbing the eDP or LVDS signal and intercepting the USB HID traffic has been on the market for quite a while).
But implausible actions and results for a player can only be attributed to luck so many times. Do 30 360noscope flick headshots in a row on a brand new account and you can be pretty sure something is wrong.
If we can get plausibility vs. luck sorted out to a degree where the method of cheating no longer matters, that's when the tide turns. Works for pure bots as well. But it's difficult to do, and probably not something every developer is able/willing to develop or invest in.
Anything that makes assumptions about player's skills runs into problems too. For any online PvP game, the skill ceiling will rise with time. What once may have been considered improbable may soon become what's consistent for the top 1% or even 0.1% of the playerbase given a few years.
As well, it can run into problems as rebalancing occurs and new abilities are released.
0: https://www.ign.com/articles/final-fantasy-14s-latest-raid-s...
But I guess the documentation and standardization are even more advanced ?
