I think at the root of it all is a far broader phenomenon than that which is far from gender specific.

In simple terms: quiet confidence doesn’t stand-out in “loud” environments were people’s attention is being sought by countless other people, especially for people who aren’t sophisticated and lived enough to recognize and value it, and the vast majority young people are such people as are (or so it seems to me at times) a large minority or even a majority of supposedly adults.

Putting it in another way, both quiet confident people are nowhere as invested into shaping the opinions of others as to spend most of their time “shouting” (and by “shouting” I mean all the ways people try and project and impression onto others, not just speaking loudly, so for example how some people always dress to impress rather than dress for themselves) and unsophisticated people are drawn to “loudness” rather than more subtle elements of how others talk, dress, make choices and act.

This stuff is behind phenomenons like Influencers, Celebrity Culture, Populist Politicians and so on, which has been pushed very hard in Western Culture for decades now.

So loud toxic masculinity posers with lots of exposure in the News Media (with the well known “Halo Effect” that people who are talked about a lot are perceived by others as important even when most of the talking about them is saying negative things) will get the attention of and influence emotional, social and/or intellectual simpletons.