Another big issue is with the studios themselves. Most shows are working right now. Most shows don't work on Sundays so the actors and producers could spend all day on Sunday getting ready and partying all night long and show up to work on Monday with a reduced schedule or in about half the shows, just take the day off. That is a day of course that crews don't get paid if they are not working.
Now, with the show being aired on Monday, it means that no one is going to shoot or work on Monday because they have to get ready and Tuesday is going to be a disaster because studios hate the idea of not being able to work for two consecutive days and that is also two days crew probably won't get paid.
Another issue is that the Video Music Awards are airing on Sunday. Do people really want to watch award shows on consecutive nights? The audiences do not exactly overlap, but there is a significant number who would normally watch both, but do those people who would overlap want to park themselves in front of the television to watch back to back nights of awards?