My understanding about Greene was that he had tools but as a position player not a 25% player when he was recruited. I don't think he was drafted out of HS. He worked under Tim Corbin, and I seriously doubt if he had to go to a smaller program he would have been the 13th pick that year or national player of the year. No doubt he would have played anywhere he went most likely with new rules stayed in FL to attend school.
He is an exception to every rule so not sure why he was used as an example.
I agree that this rule may help regional schools where otherwise good players would have looked elsewhere, however, my understanding is that schools in the south are so much less $$ than northern schools to attend, they will still head south.
Bottom line is, go where the opportunity presents itself for you to play and not sit. That doesn't change.
I too would not know how to advise my son if he was being recruited these days.