They didn't mention the fact that successful younger males are dating multiple women at once. That's another factor.
Is it? Are open relationships that statistically significant?
I think we're talking about ambiguous relationships, not open ones.
So situations where women think they're in a relationship, but the man does not (or not with them). Again, is this statistically significant? Are women's standards for what qualifies as a relationship low enough that they think they're in one with 1/2, 1/3, or even less, of a man's time?
I'm willing to bet that it contributes to the total in a way which isn't negligible.
I guess, but there's a vast gulf between "isn't negligible" and "30% vs. 60%"