What I'm talking about is a kind of "grassroots" disparity of opportunity. It's not necessarily the same as a "systemic" disparity of opportunity. The former can often be available to people who are literally poorer than the poor. (As has been the case for Chinese immigrants at times.) Irish Traditional music contains another example of the former.
Often, disparities can be a mix of these two things.
I agree with everything you said here, but you're presenting it as a disagreement, so I'm a little bit confused
I'm glad you're feeling a little bit confused. Often, this can be a good sign!
The problem with how such disparities are talked about and acted upon, is that the complexity of the situation is often downplayed or drastically underestimated, then combined with a punitive attitude of blame and compensation. This isn't how these things are known to work. The best way to transmit cultural knowledge is through some form of competition. (Friendly and peaceful are best, of course.)