"men being as masculine as possible is an answer to all of the problems of the world"
That's basically Peterson's argument in a nutshell.
There's a fair amount of conflict in Western psychology and neurology where young men aren't seeking female partners for sex and child rearing. Its sort of reductionism where a male is supposed to work and foster children, I mean its basically the cornerstone of civilization and has somewhat of rooted thinking in nationalism, where the nation thru species propagation will become stronger and rule over lesser nations. You have a connection with economics as well where people are supposed to have children to fill the working class ranks.
There are obviously religious connections as well to that overall idea.
So really "gay" people from sort of a 1950s era level of thinking are people who aren't going to reproduce. We obviously know this to be untrue, as Science and social freedoms have allowed various persons to have children, etc.
The problem is more complex because Work and Economy has been shown to be unsustainable. Essentially men are supposed to work for a long time (decades) but with companies and markets being what they are, and really with the nature of work changing over the last 50 years, society has created an environment where child rearing is undesirable. The government really doesn't care about children either. So you have a declining birth rate.
I believe that really Western civilization really isn't about choice, I mean you just have to look at abortion deregulation in the US to support that. So that's where I think the "gay" community fits in, where largely its a deviant community, from a top down perspective (runaway individualism as a crack in the foundation of society perhaps).
Within the hierarchy, the top level refuses to believe that the pyramid has collapsed, I mean the social engine is still turning away, but I mean you just have to look at TFW/foreign workers in both Canada and the US (and probably Europe) to know something is terribly wrong. There are other inconvenient truths, war, climate change, disease, famine etc. The horse has left the stable a long time ago.