Even though that's true, the fact that pixelbot/colorbot type aimbots are still popular shows that they are perfectly effective. In fact, if you really want to remain undetected for long periods of time, "wallhack" style cheats have the obvious downside that someone analyzing the replays can easily see that you are routinely locking onto (nearly) the exact positions of enemies behind walls. This is inevitable even if you try to avoid it because without actually looking at the pixels on screen it's going to be hard for an aimbot to be pretty sure that you can actually "see" the target behind whatever obstacles or fog is on screen. This obviously can't happen if you are cheating using only the actual game output.

In the end, what matters to the cheater is being able to win, so if a pixelbot will do the trick and be less detectable, it's probably worth more rather than less. I believe it's just a matter of time before the pieces come together. (Of course, it has to actually be effective in order to really be worth more, but I think that's largely a function of how good the actual aimbot portion can be, and I really think with how good and fast ML has gotten you could really do a lot better these days.)