I think it's a relevant question and I think the op has every right to ask it without being ridiculed or treated as a racist!
I taught in a secondary school like this and it was very very tough. I, and many of the staff felt we would never consider sending our own child to that school.
A huge problem was it was badly managed, to be fair. But we were in an area where most of the local schools were selective (this was a few years ago, don't know if things have changed in this regard). So our school was the dumping ground for all the "undesirables" that no one else wanted, either because of poor behaviour or poor achievement, so we had a huge proportion of very difficult and challenging pupils.
Having so many kids with english as a second language was an enormous challenge. Many of the kids weren't wonderfully bilingual with all the plusses that brings. They had their first language and simply struggled enormously with English. This did have an impact on the lessons. A huge one.
I also think it's ridiculously naIve to say "kids are colour blind tbh,"
Many of the kids I taught were not. They were utterly vile to each other. (paler skinned) black kids took the piss massively out of darker skinned black kids. The poor kids from somalia were on the receiving end of most racist comments. West Indians hated Africans, African hated Indians. God it was truly frightening and depressing. I had never encountered racisism before (or since) anything like what I experienced in this school. Actually, only very rarely were white kids involved. (I guess being in the minority they would have been stupid to say anything, but only rarely did they receive any comments. Most of the white kids, I guess to fit in, adopted the same accent/style of talking as their black friends)
There was probably one class per year of the "hard working immigrant who saw education as a valuable means to achieve success stereotype". But unfortunately most of the other kids were from homes which didn't place any value on educational achievement, so no value in it, had few ambitions, and in fact held the teachers, especially female ones, in complete derision and contempt.
I would not rule out all schools with a high number of children from ethnic minorities, but I would be cautious, and think it's perfectly reasonable and sensible. I think issues like the level of English language ability and integration are ones that need careful consideration.