There are some unique reasons that men are more lonely, even if we all are as well. They don’t show weakness to their friends or help each other out as much emotionally. The vast majority of men have no support network for this sort of thing. The bros will help out materially, but less so emotionally.
Capitalism is still more to blame than gender for lonely men, but they have an extra disadvantage. We all need societal change, but men have a harder time finding that sense of belonging than women. It’s how gangs, militaries, and fascists lure in boys. They promise a place for men, even if it’s as a disposable tool. Liberals used to promise men a place as successful workers, but that place has disappeared with the middle class, while fascists get to blame feminists for capitalism’s effects.