Feel like we're going to end up with 3 big 20ish school conferences: B10, SEC, and the Big Pac (the 2023 B12 plus the remainder of the Pac12). Big Pac will be a second tier league, but it will be solid and I bet they'll end up getting a playoff spot once expansion happens.
Notre Dame is really the key factor. Like others have said, if Notre Dame goes to the B10 then Stanford probably tags along with them. If they don't end up in the ACC, then I honestly don't see that league surviving as a major football conference, and anticipate that the SEC will raid it's main football schools to keep pace with the B10. Clemson, FSU, and Miami would be the most likely schools in this scenario, with UNC being a possibility (depending how loyal they are to the other Carolina schools). The remaining ACC schools will form a solid basketball league.
Oregon and Washington are the main wild cards. B10 is the most likely landing spot, but I could also see that league passing and thus relegating these schools to the Big Pac. It all depends on what Notre Dame does and how quickly and willing these conferences are to expand (as well as money of course).