Well, I think in terms of the pertinent issues for this thread, one can ignore the issue of whether cloth masks are effective or not in preventing the spread of Covid-19. It is probably sufficient to note that what
@Lindberg says about the cause of unruly passengers is true. The majority of the complaints are related to the mask mandate. And secondly to note that a substantial fraction of the population does not believe the masks really work (whether that is true or not).
Thus it is an attempt at strict enforcement of an FAA policy which is rather unpopular. That is the sort of situation which is likely to lead to unruly behavior.
I also tend to agree that packing people in on commercial flights is a contributing factor to unruly behavior as well. Puts most people in a bad mood to start with. It is not a pleasant experience. I frankly preferred it when the middle seats were all left open, but that is obviously not economically sustainable at those low prices.