IMO it will be a close fight between AA, Delta, and SWA.
Delta only has one hub getting hit but it is the largest of the hubs. I also feel there could be some shenanigans that will occur with negotiation season starting. You already see it with management blaming last month's issues on the pilot contract.
AA and SWA have multiple hubs getting hit sequentially. DTW, CLT, DCA for AA and DAL, BNA, ATL, and BWI for SWA.
Will be interested to watch. This is assuming I have electricity to watch the chaos unfold...