Really it's the NCAA trying to hold onto relevance. The prospect of the G-League or a competitor providing that HS to pro-transition in the revenue sports, particularly with their golden goose, D1 Basketball, more or less forced their hand to adopt this or face acceleration in the transition of the top athletes fleeing the college ranks for their pre-pro prep.
There will be some correction in this at some point, where boosters are going to be less interested in dropping their own wealth to fund the 2nd and 3rd string players, even at the major schools, because while saying I fund Texas football might have some cache, it's not the same as saying I'm paying our first string or our Heisman trophy candidate, etc. It will naturally start to flow players in search of additional playing time and the addition name, image and likeness opportunity that comes with it.
People figuring out just what they can get away with is still going on, it'll get worse the next couple of years before it stabilizes. Where it'll be a real difference maker is in the non-football/men's basketball sports. If you go to a school that has outsized popularity for a non-traditional revenue sport (think UConn Women's Basketball; BC Hockey; etc) then those players will have much more NIL opportunity than other schools and it'll be more likely to funnel talent to those schools.