Actually, when I am around women I often feel pressured to grow down because often, when I try to maintain an adult-like atmosphere I seem to come off as some sort of rapist. When I am with my friends it really depends on how exhausted we are, we can be extremely immature, and drunkards, but as soon as we tire ourselves out we get into sophisticated conversations about quantum theory and universal law.
if you notice that men near you are having a tough time being an adult, disregard previous experience and try to get them to talk about a topic worth debating. Men love to debate and once you get them started they might have a hard time stopping, just make sure not to get offended, if they say anything negative toward you it's probably to make a point. If they act immature they are probably just being fun.