Segregation happens for all kinds of reasons, not only because of colour. Till in the sixties/seventies last century denominations were the great divide here in my country. With plenty of drama. The joke was that even goat breeding needed to happen in denominational determined committees. It was damn strict, and lots of interdenominational marriages came with shunning and never talking to kids or parents again.
Not fitting in in one of the groups is probably the fate of the spazz. I2 may be the only segregated group I fit in.
The problem is not the clustering in groups, most people do need a wider social network to thrive in. The problem is when groups become cages. Either cages where people don't dare coming out of, or cages where people are put in by others. When the fear factor becomes an issue, things get nasty.