I don't think I understand what you mean. If that were the case, wouldn't teen girls have the same issue? I know it's hard to convey sincerity by text so to be clear I'm not trying to be glib, genuinely curious about your ideas here.

...because we now are happy that gay people can leave the closet and overcome the threats that would keep them there, straight men can't share emotions?

There are gay women. Why are friendships between women not a threat to the "no homo" need?

There is evidence that the intimacy (especially physical intimacy) of male friendships declined starting in the 90s as more gay people left the closet and slowly worked towards social acceptance. But the "no homo, bro" reaction is entirely self inflicted and has absolutely nothing to do with a sexualized society. I'd actually wager that the straight men who spend the most time around out gay men are the least likely to feel the need to resist male intimacy out of a fear of a threat to their sexuality.