The issue is that for a lot of lonely men (probably most), the issue is social ineptitude, hangups and all the issues in modern life that make forming connections hard. That impacts their ability to form friendships, find romantic partners and to get casual sex.
Some men might be able to get casual sex but not friendships, but I doubt that's true for most.
Also all the "progressives" who use penis size as insults. Like, are you trying to promote toxic masculinity?