It's the same tenuous situation the Big 12 was in last year, when all of W Virginia (ACC) and Kansas/Iowa St (B1G, though that now seems laughable) and Oklahoma St / Texas Tech / Kansas St / TCU (PAC12) all tried to leave and any of them leaving would have been a death blow.

Given that recent experience, I hesitate to be overly quick in declaring a conference's demise, but I do think they're definitely in a tenuous spot.