@AmblesideMom We are in the exact same boat as you-- from the South, no ties to BS on either side of family, not at all wealthy, but right there in the middle economically.
Our take is that some BS’s have more of the NE wealth and some have less – some are more diverse geographically than others, even though the stats would put them at being similar. My DS was very quiet and studious–and ended up in a school perfect for him. He fits in well and has friends who are on complete opposite sides of the spectrum from financial, ethnic and religious aspects. His group is very diverse. I truly think it depends on the “fit” we all talk about more than anything else.
If you’d like to PM me, I would be happy to talk about our personal experiences, although it seems the crew has pretty much summed up the answer to your question. Welcome to the BS forum!