But this doesn't make sense on its own--the integrity of the walls of the Man Box have been going down over the past twenty years, but the suicide rate has been going up over the same period.

If it's loneliness, well, everyone's lonely, so it doesn't explain why the Man Box has that much to do with it: https://www.npr.org/sections/health-shots/2020/01/23/798676465/most-americans-are-lonely-and-our-workplace-culture-may-not-be-helping

The explanations might have a degree of truth to them, but they feel like they're trying to paste an ideological commitment onto reality and seeing what can be explained with it (which is maybe more than nothing, but it's very unsatisfying when you have two trends going in opposite directions and a claim that one exacerbates rather than diminishes the other).