Because the gender socialization of a binary patriarchal society demands it. And yes, you've completely misunderstood what I said. I even highlighted it - I'm not sure why it's unclear?
"I wouldn't call that toxic femininity because it is not a reflection of inherently feminine characteristics being taken to an unhealthy extreme in the way that "toxic masculinity" is otherwise just fine masculine characteristics taken to an unhealthy extreme."
Baby boys have been repeatedly shown in studies to be more inherently emotional than baby girls. It seems that once again, culture has a heavy hand, although I agree that there is a huge spectrum of traditional gender that we all exist on, with most people having a mix of traits. Individual differences are much more pronounced than binary gender ones when you account for socialization.
There's not a single thing that I've ever said that disagrees with your assessment that men and all human beings have both good and not so good parts. That was the main point of my original comment.