A buddy of mine owns a cheat selling website for FPS games. He's actually thinking about shutting down his site after 9 years of making hacks. Because of Easy AntiCheat, and Battle Eye. Hackers like him are having a real hard time bypassing those AC/s because they use kernel drivers. Most of his cheats run off of manipulating Direct X to draw visuals like boxes, and skeletons on players. Aimbots calculate X,Y,Z, coordinates of a player in the game. All of which can be effectively killed by making a kernel driver AC.
Not only that, but game dev's are also getting smarter. They are going after the hack creators in multiple ways. One way is to threaten legal action, as was the case my buddy ran into. He was sued by Epic. A small-time site and coder is no match for the legal juggernaut that is Epic right now. The other way that Dev's are hitting back is to regularly patch their games. If it takes you 2-3 hours to update a game each time a patch comes online, and the game patches 3-x a week, well the coder may just throw in the towel altogether.
So to summarize, could you make your own hacks? Yes. But these are some of the many challenges you'd face even IF you somehow got to that level of knowledge.