The simple answer is yes that they wanted a Sunday finish for TV. CBS would also like the tournament to end at maybe 6:45, quick green jacket ceremony in Butler Cabin, and an on-time lead in/start to 60 Minutes one of their top rated shows. Too early of a Masters finish loses the lead-in to 60 Minutes and too late will lose non-golf 60 Minutes viewers. Only the NFL can mess with 60 Minutes.
Personally, I'm glad this is the goal because I don't have time to watch golf tomorrow afternoon. It's entertainment.