I think progressives never thought about this because we banked on immigration and demographic change allowing us to win culturally and electorally but the issue is immigrants tend to be overwhelmingly male, that is how Trump won actually he won over a lot of Hispanic,Black,Asian and indigenous men who feel humiliated by a new culture, economy and world.
So what can we do rhetorically and policy wise to win more young men over ?
You need to make it fun and engaging for them. That is what the far right is doining. You and I might find it reprehensible, but they het som much traction bu having fun and giving young men a purpose and the feeling that they are doing something to netter themselves and their commuity.
How you go about that I dont know. In my local area we are focusing on having fun partiets and going out together as a group instead of just being political nerds in our own little grottos. Som far it seems to be working.
Tl;dr: Have fun visibly and invite them to join you. It takes forever, but at least you have fun while doing it.