I think part of the issue is that Obama’s policies were often criticized not directly, but by using oddly specific made-up statistics. By arguing with those imaginary statistics (but not the implied policy criticism), it often ended up making that implied criticism point back to a point in time prior to the Obama administration, whether or not the implied criticism was ever valid in the first place.
I don’t think the veracity of the blame-assignment is relevant. Partisans are going to be partisan.
Well, sure. But part of the problem of Democrats spending more time arguing against made up conspiracy theories is that they spend less time arguing the merits of the policy. Which means the Dems (and the public) may assume their policies are good simply because the arguments being made against it have no merit. And that’s not necessarily true at all. I wish people had challenged Obama’s policies more on the merit of those policies–it may have actually shifted the political discussion and gotten something changed.