Look at the rosters in women's tennis among the top teams: they are now bringing in international pro-level players and paying them enough where it is a great value proposition for their development.
College can offer housing, education, training, coaching, facilities, medical and transportation that pro players usually have to pay for on their own. Thus it only takes a modest NIL offer on top of that to find a few ringers willing to go this route. Because most mid-to-low tier pros lose money annually because of the expenses listed above. Especially when they are starting out. And with new NIL rules, they still have access to sponsorships, and can play on the pro circuit all summer and often the fall as well.
Just a couple of years ago there used to be maybe 2 or 3 college players with a UTR above 11. Now there are 15:
UNC did not get worse; the top SEC teams got better. Auburn has four players in the top 20. LSU has 3. 17 of the top 20 players are SEC, which used to be an afterthought in women's tennis.