I think a strategy to break up the ACC (or at least, get some schools out of the ACC) might be starting to emerge, and the details are all mirroring what happened with the B12 around OUT and the PAC from USCLA to their collapse.
First, ESPN declines their option on the ACC deal after 2027. Is there anyone that can step in with enough money and linear access to provide a competitive deal? That's ultimately what killed the PAC. Obviously, ESPN is out of the equation, leaving Fox, CBS, and NBC. Fox would probably be fine bolstering the B10 and B12.
Second, FSU, Clemson and anyone else who wants to jump in fight the ACC in court over the GOR. Not having a media deal in place, and not having any offers that keep pace with at least the B12, would add fuel to the fire and give their case more legitimacy.
Third, the B10, B12 and SEC sniff around their desired programs. The B10 wants UNC and UVA. The SEC, Clemson and FSU. Personally, I think the SEC takes Miami to keep the B10 out of Florida and either NC State or VTech to even out the numbers. The B12 goes after Pitt, Louisville, the other of NC State/VTech and then 1 more (Duke? Syracuse?). With nothing in place after 2027 (and bad offers), the mid-tier teams have a reason to look out for themselves.
Fourth, approach ND and the schools not being courted by the other conferences about a reconstituted ACC. ND is the key here as the anchor of the conference. They need the ACC as a home for their non-football sports and a handful of football games a year to fill out their schedule. Money isn't the biggest thing (they get ~$17m/year from the ACC, $50m from their NBC deal), but football independence is huge. They'd have two long-standing rivals in the new ACC (BC, Stanford), and let them pick anyone they want to fill out the rest of the conference.
Fifth, assuming the GOR is still an obstacle (court cases like this can take years), they'd need to get 12 schools on board with dissolving the conference. I've outlined how to get 11 (10 to the B10, SEC or B12, plus ND), they'd just need 1 of the left-behind schools to accept. Going back to step 1, they don't have a deal post 2027, and no offers that a majority of the conference is going to accept.