ABC owns the controlling interest in ESPN (80%). They're spinning the end of MNF as buyout for $1.1b, but this is nothing more than a programming decision by ABC, which is owned by Disney. Does ABC really have so much compelling entertainment content that they need the Monday night slot? I don't think so. Why move MNF to cable?
I wonder if the teams playing on Monday Night when ESPN takes over will still be allowed to show the game on local TV. Here in Colorado when the Broncos are on ESPN Sunday Night our local ABC station is allowed to simulcast for those who do not have cable.
The NFL told Disney they wanted to move the better prime time games to Sunday night. Disney declined that package so it went to NBC. Disney still had MNF but since it would be given the lesser games they decided it wasn't worth putting on ABC.