That’s a different threat vector, but was also eliminated in other games. RuneScape devs, let’s face it, are really stupid.
For auto clickers, and the like, just make sure whatever is happening is possible for a human to do, auto clickers are faster than humans so they’re easy to catch. If they’re using it to move, that’s a predictable thing that can be fixed by changing the terrain slightly like wow did to catch and ban a few million bots at a time.
Kernel anti cheat would not be effective against that vector anyway, as memory isn’t changed in most cases.
They don’t have to be faster than humans though. Again it’s the whole cat and mouse thing.
Kernel level anti cheat could detect the app sending the mouse messages or detect non hardware messages and would have rendered them absolutely useless. Could also detect things reading apps pixels which is how they functioned.