Men don’t need friends. Men need family. You have some casual friends at work then spend your quality time with family and maybe some childhood friends you kept in touch with. This is the natural way of things.
What you call natural is societal behaviour that is specific to western society of this day and age. Even in our own society looking three generations back that "nature" looked different and if you cared to look elsewhere than where you live you'd find that what you call "natural" does not exist in certain other cultures as well right now.
Be careful to mistake something feeling natural to you (because you know no different) to something actually being natural in an evolutionary biological sense. Those two are very different bars to clear in terms of proof.
Men want people they would willingly die for, family and only the closest of friends qualify. Western individualism has, in many ways, lost that very basic need.
This is why men who have been through experiences have a tendency to become close friends. Think about former war buddies. Sports is, in many ways, a simulated war scenario.
A significant percentage of men not having any close friends feels like a recent development in the last 1-2 generations.
The take that GP is expressing feels like a very post 1980s thing.
None of those friends and support groups would be "close" friends per TFA's definition because they weren't acting in the quasi-therapist role that the author apparently thinks is required of "close" friends. Yet clearly those relationships filled the need.
Cancer and cancer treatment was a bitch. The importance of friends (and family) became evident to me during that time. YMMV I guess.
It's not natural what we do in our modern society at all btw.
Tribes were very normal and tribes never just focused on family.
Animal kingdom also shows plenty of group and tribe behavior
If that was said by married man then I'd joke that he needs a little longer leash