It’s disappointing to read that the crew didn’t seem interested in enforcing the regulations.
Frankly, I don't blame them. Pax not wearing masks, despite having been told to do so, are likely to be drunk, or part of the anti-mask brigade, or simply don't give a damn, or all three; they're likely to be aggressive and disruptive if challenged even in the gentlest way; crew is then faced with either escalating to the point of landing and calling police with enormous delay and further aggression and disruption, or continuing anyway; which would the other pax prefer?