Let me put another thought to you. When I was on Google Plus, I had more than 38,000 followers. Three or four times a week, one of my posts would get up to 1.5 million reads and close to 10K shares. The maximum number of comments was 500., and they would be used up. Everybody wanted an answer.
It was impossible for me to respond to everybody.
Very few human beings have a capacity for more than 3 or 4 friends. We are very busy. Extroverts tend to have a wider circle of frriends, but they're not that close.
So when people befriend those that they have nothing in common with, they're giving very precious time away to someone that they don't particularly enjoy.
You're also saying that people learn from other people. In my 71 years on this earth, I have never seen that. People learn from reading, from goiing to college, but in terms of friendship and social relationships? No, they dont learn.
I don't have anything against making friends with people who are different to us. I just think it's an unrealistic request.