I know an analyst that covers Disney stock and he spends lots of time talking to ESPN management. He says they would love to upgrade the programming, but there just isn't a way to keep two networks on 24 hours a day and not have dead spots. One thing that has really gotten to them is the leagues are basically tightening the screws every year in terms of how much they can show games, when they can show them, and even how many times they can show them. Add to that every second rate activity or league thinks they are worth money so they won't give rights cheap anymore just for the free exposure. They have tried to do deals with all the minor leagues and none are willing to talk, but they all wanted live games at times when there already was plenty of programming so they had to walk away from it. Their idea was that almost every weekday instead of those worthless programs show a AAA or AA game live with the marketing of "watch the future stars of the game", but it got vetoed because the leagues would rather insist on having one game in prime time a week than five or more during lesser hours.
I am not saying they aren't immune to criticism, but lets face it they really have little choice. What else can they show, everything original costs money.