I agree the Democrats are dominated by neoliberals (Biden being one, as were Obama and the Clintons neoliberal), and that their economic policies have the same upshot as the Republicans', namely entrenchment of American plutocracy.
In this particular election, I expect the votes for third-party candidates to be especially minimal, because of the much greater tribalism and partisan divide this time. Certainly, voting for Biden won't end the plutocracy, but it will help get rid of Trump. Trump does far more damage than Biden and the neoliberals ever could.
The media ignore votes for third-party candidates along with all the nonvoters. Of course, there could be no ignoring those votes if a third-party candidate won, but there's no hope whatsoever of that happening in 2020.