It is a bold move, but it's also one that can (likely) only be made when you're closer to the media contract expirations/negotiations.
If FOX wanted to make it happen, they could.
Of course, you're starting from the premise that neither conference would jettison members, which may be a fair premise.
Which option produces the biggest TV contract?
Option 1: B1G absorbs top of PAC
Option 2: PAC absorbs top of B1G
Option 3: Top 2/3 of both leagues create new superconference
Option 4: PAC & B1G create some sort of alliance
Option 3 is probably the most valuable, but is, by far, the hardest to coordinate. Between 1 & 2, I just don't know which one would be more valuable - it's not an easy call.
Option 4 could be structured so many ways, it's hard to say what the TV contracts could be (and do you do any sort of revenue share?). As one of many possible options, I think a relegation setup with upper/lower divisions in each conference and a coordinated scheduling arrangement between conferences could produce some great early season games between heavyweights (creating value), and you'd get some compelling late season games between unranked teams - (adding value to games that are currently nearly valueless in broadcast terms).