https://www.espn.com/mens-college-basketball/story/_/id/36018936/after-record-1st-round-men-tournament-ratings-23
I don't think the networks would want this tournament to die, but with conference realignment who knows.
I think it's more likely that the networks are fighting over getting the tournament than there's a risk it dies. It's not like March is a high time for other sports.