I think Gabby is getting valuable minutes and Geno obviously wants her to get some experience. She's going to be a big part of the team the next three years. He put her in the ND game when it was definitely still in question - in the first half, I think UConn was up by 4. He wasn't putting Edwards in at that time, that's for sure. And he didn't need to put her in - no one was in foul trouble, Stokes and Tuck were both playing great. So clearly he wants to work her in.
I think we forget what a luxury it is to actually have a bench, because it's been so long since there's been more than a one or two player bench. I think in Geno's ideal world he would use freshmen exactly how he is this year with Williams...get her experience in big games, play her more minutes in blowouts, and get her ready to contribute for three years. What he had to do out of necessity with Bria and Stef is out of the norm for him.
Look at how he used Maria Conlon as a freshman...she got into a lot of games, but definitely wasn't a key player as a freshman (or a sophomore). But she earned her time and played a ton as a junior and senior.