You wonder if CBS really wants to get into the college football market or not. SEC is on CBS through 2023 and then they are done. They have CBS Sports Network and of course big CBS to play games on. If remaining 8 were combined with ACC or Pac 12 remnants CBS and Fox could combine to pay decent money to those schools for lots of content that could span all sorts of time zones. These schools need to get additional media to compete for rights otherwise the ESPN monopoly will be basically complete.
I doubt CBS wants to stay totally out of college football. I think they were paying pretty well for the SEC game of the week, and when ESPN tripled them or whatever, they were probably like, WTAF? There really aren't any normal shows or alternative sports that are going to draw anywhere nearly as well as college football on a Saturday afternoon, so I'll bet they're looking for options.