I'll use the term "friends" to mean just that as well as something more.

Ive learned over the years that there is no singular reliable pool from which to draw from to make friends.

I've also learned that no one can predict with certainty whether or not friendships will be successful. All we can do is take it one step at a time.

Oh sure you can set some basic requirements in a friend. Must not be older/younger than self. Must have a degree. Must like (fill in the blank) but even then no one can predict with certainty the relationship will become more.

I do know that joining a group, of like-minded people, can make you new friends. The benefit of putting oneself into that situation is "more learning". We learn about ourselves. We learn about other people. That's a pretty good benefit IMO. :-)