TL;DR: IME, outside of the USA, high school friends > uni friends. I grew up in Italy and lived in Australia for many years, I have the impression that in both

TL;DR: IME, outside of the USA, high school friends > uni friends. I grew up in Italy and lived in Australia for many years, I have the impression that in both of these countries, high school has a bigger role than uni when it comes to life-long friendships. This is attested by the fact that in both countries you see a lot of very expensive private high schools (I attended one of those). But I've heard that in the US, uni (or "college" as it's called there) is the main networking environment for most people. I have friends from many different countries and from what I've heard, in this case the USA are the exception to the rule.