The "enforced monogamy" thing is actually to do with social trends. It's basically an outcropping of greater male variance theory, which postulates that the reason human history has been overwhelmingly patriarchal is because there's far more male geniuses to take charge, and we just don't really notice the similarly numerous droves of idiots. His relevant statement is "half the men fail. And nobody cares about the men who fail". Essentially, incels didn't used to be a problem for society because there wasn't enough interconnectivity in the world to render below-average "undatable" men an issue, because there simply weren't enough men to chase. That top 20% of men getting 80% of the women's interest wasn't an issue because women generally wouldn't know about enough of them to drive the dating pool down so far. But thanks to recent social trends, the dating pool is overwhelmingly enlarged, allowing for that top 20% to have access to the
real majority of women, and the sheer size of the dating pool makes it so that the bottom 40% or so are doomed to involuntary celibacy.
What the enforced monogamy is is widespread slutshaming and socially pressuring people to marry young, so that the degree of below-average needed to reach the cutoff point of being "undatable" gets far enough that it doesn't have a chance of causing widespread issues. Japan's got the "marry young" part down
extremely strongly, with a woman past 25 (generally referred to as a "Christmas Cake") being virtually impossible to marry.
Most of this is me expanding on the logic entirely out of my ass, by the way. Basically trying to justify the view, because I haven't read/watched his actual defense of the issue. Which is
here, by the way, but I'm not redoing the post for that because I like trying to explain things with my own reasoning. What I
will bring up from there is that "enforced monogamy" is actually a decades-old academic term for socially enforced monogamous behavior, as opposed to government-enforced like we retain, or evolutionarily enforced like we lack. He actually has academic papers cited, though they appear to be paywalled. It's almost like people are forgetting he's actually a
professor of psychology, specializing in abnormal and social psychology. You know, an actual certified expert on the topics he tends to talk about? Social ills and psychologically-distinguished minorities?
He has a website. And a YouTube channel. It's not exactly difficult to find his actual words on subjects
from him.