To me, it's been their recent propensity to create news, rather than just report it. Whether it be non-stop Tim Tebow, Manziel Mania, or even something like this whole "kneeling for the anthem" crap, ESPN makes sure that their "pundits" give as hot of a take as possible, so as to insert themselves into the story. Or, the example from a few years ago, where ESPN's own Ron Jaworski made comments about Colin Kaepernick being a top 10 All Time quarterback. (How silly that sounds now) Basically, the entire network seized upon it and it became one of the lead stories of the day, prompting interviews, reactions, and alternate takes from their entire cadre of "experts." Completely manufactured news. People get tired of that crap, or at least some of them do.
Shows like First Take are another issue. I understand why people might watch them initially. Conflict is a big draw, but after a while, you notice that that's all they have; conflict for conflict's sake with very little substance other than that. It becomes almost insulting to the viewers intelligence.