I've watched the Act Man on and off for a while now, his content is informative and pretty entertaining, sad to se him going through this. I doubt Quantum has any direct involvement with Act Man's demonetization, but there is one thing he does seem to know how to do, and thats cover his ass. Probably one of the main reasons he hasn't been banned, demonetized, or targeted by YT directly; he knows how to manipulate the system.
There are a few reasons why I think Act Man was targeted by YT instead of Quantum, multiple have already been stated, like YT trying to avoid a possible larger "racism" fiasco; based on what I've noticed the guy is petty enough to take it that far. Though I think the main reason is as the old saying goes, "you never bite the hand that feeds you." Act Man thought that if he put the evidence out there and got YT's attention by calling them out, they would do the right thing. Unfortunately he miscalculated, and painted a target on his own back instead