Re: men and friends (or lack of!) it is actually true that as men get older their friendship group dwindles (for many of them,) usually as more and more of them get married, and see each other less/spend more time with the wife and kids, and in-laws, and parents etc, And it does start in their mid 30s.
Women tend to have more friends as they mix in more social groups/mum and baby groups etc. Even so that doesn't mean that every man 35+ has no friends, and that every woman 35+ has oodles of friends.
I had lots of friends right up to my late 30s. At least 4-7 friends at any give time.
Once I hit 40, I don't know what happened, or why, but I found myself friendless. It was just me and the DC, and DH. I saw half a dozen or so family members once or twice a month, but was really friendless. I had 3 or 4 OK-ish work colleagues, and we would have the odd work do 3 times a year, but none of them were 'friends.' This lasted about 9-10 years.
DH went down the same route.. But his friendship group dried up by 34-35... So 4 or 5 years before mine did. He had lots of friends up to about 35, but for him there was nothing for about 13-14 years. Just 2-3 work colleagues he would see socially 2-3 times a year, and his family.
Just this past 10 years (since around 48-49,) me and DH have made new friends after moving to a little village and joining a couple of social groups. He also has a good friend at work who he goes to the pub with once a month, and I have reconnected with an old school friend (back in 2015) who I hadn't seen since school. I see her twice a month. We also get on well with neighbours, and have drinks at the pub with them twice a month or so...
Friendships/friends come in peaks and troughs over the years for many. But yeah, I think some men do tend to have a lack o friends moreso than women, but as I said, it's not a given. Some men have many friends, and some women have few. (And women can struggle to make friendships/keep existing ones after 38-40.)
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