yes, segregation-by-law doesn't exist anymore in the USA (personal preferences of police officers in LA aside), yet there is a phenomenon of poor black and hispanic kids in Oakland going to school which is predominantly attended only by other poor black and hispanic kids. Segregation-by-de-facto-conditions-of-life?
Segregation in common English, at least to my ears, implies some degree of malicious intent. We don't have laws that do this anymore, but there are other possibilities such as racist real estate agents, or the 'strategic' placement of highways between neighborhoods (see Chicago, from what I understand).
Your usage is technically correct, but I think it carries an implication that is not necessarily supported.
I dunno -- there's a lot of talk of self-segregation in the last decade or two. I think that gets lumped in with general segregation in this day and age (certainly it didn't 50 years ago), and I don't think that form of segregation implies any malicious intent.
