He makes many good points, though I don't completely agree with all of them. I definitely think that the left needs to do a better job of listening and trying to understanding those who think differently. I think that applies to the right as well, though.
I raised my eyebrow at his insistence that Bernie Sanders would have won. Of course I would have raised my eyebrow if you told me Donald Trump would be president in 2014
Agreed, I think both Clinton and Sanders were flawed messengers, and that neither of them (or the other jokers running for the nomination) were the best Democratic candidate for 2016. Who was the best? I have no idea.