Sooooo. What lessons did Democrats learn from 2016 that they can apply in 2020?

[Hindsight was 2020]

I don't see where they've learned anything. 

They SHOULD have learned that since there are more conservatives than liberals in America, they need to be a "big tent" party.  That means tolerating centrists, giving them real roles in the party, and recognizing that, at times, a moderate compromise is better than no advancement at all. 

With all due respect what the f*** are you talking about, we nominated the most centrist ticket we could of had.

[Hindsight was 2020]

-Not to nominate a criminal
-Not to insult millions of Americans
-Not to nominate someone with baggage and a high unfavorability rating
-Not to pick a nominee who will suppress the Progressive wing of the party

That is just a few of them.

Basically this and some other things mentioned in this thread. I'd also add that their obsession with social issues is really hurting them in the rural and suburban areas. While I don't think they will move to the right when it comes to social issues, they would do best if they focused on economic issues.

What obsession? I'm sorry but just because Trump won doesn't mean reality gets rewritten. In all these major social issues from trans-bathrooms, gays being denied services, etc... have all been made issues by cons not libs