Identity politics are just a way to appear leftwing while not offending their big money donors. It isn't just that identity politics is there, it is that it isn't even authentic. They Democrats don't believe in it really. The Republicans DO enthusiastically embrace identity politics and that seems to work for them.
And outside of the most blue districts they have been downplaying it for decades anyway, choosing to focus on how bad the Republicans are and the barbarians are at the gates and they are the last line of defense and blah blah. So they are the party that defends the status quo when they are not doing the identity politics thing which...has its own problems.
Most of the sorts of issues that I think would make the Democrats popular and an actual party just aren't feasible politically because it goes against their donors, even if it would be popular among their voters. So what to do? I don't know. If I knew the answer to that I wouldn't be sitting here on Surly.