That, indeed, is a big part of the problem. But it’s more than just Democratic elites that tripped up the Democratic Party as exemplified by Hilary Clinton, it has a lot to do with the electoral process itself.
While Democrats have mainly focused on sound policies, Republicans have concentrated on gaming the system, voter suppression and gerrymandering — hugely effective. Moreover they applied very sophisticated AI programs to identify voter’s emotional weak points and then came at those weak points with slickly concocted fake news.
Thus they have captured the government psychologically and mechanically from the ground up in every place not overwhelmingly Democratic.