If you assume everyone is at 16 (meaning the Big 12 has added the 4C schools) then their are only 12 spots and that list contained exactly 12 but didn’t include Oregon, Washington, Stanford, or Cal.
If the Big 12 hadn’t expanded then those numbers could be really clean, but it never works that way in real life.
I do think Syracuse, Boston College, and Wake Forest are most likely to be left out though. Maybe they join up with the Big East and get them to a nice 16 team league as well with STL or VCU.
If ND joins anytime soon my money would be on them going to the Big Ten with Stanford, Oregon, and Washington. Leaving the ACC intact for now. SEC eventually takes FSU/Clemson/UNC/UVA then the ACC can still backfill with WVU/Cincy/UCF/UConn and the Big 12 grabs Memphis/Tulane/SDSU/Cal.
That gets you to 4 conferences of 72, not 60. The only way we go down to 60 is if the SEC/B1G say fuck everyone else and just do an NFL type Super Bowl both expanding to 30 each, or if there is a true breakaway league formed with the biggest brands, cutting away the Mississippi States and Purdues of the world where invites are strategically considered by the blueblood/near bluebloods and TV partners looking at markets, ratings, history, and growth potential.