The problem for Biden is that of those young people 2/3 identify as socialists, a la Sander and Ocasio-Cortez, not his kind of "Reagan republican" -democrats.

The thing I'm seeing is a lot of leftist either not voting, writing in Sanders (where possible) or voting Green (where possible). Some are even voting for Trump in order to bring down the DNC and capture the party. They are not going to vote for Biden just because he's (barely) not Trump.

Using words of hyperbole, the young seem to feel that if the choice is between beer house type of fascism (Trump) and corporate type of fascism (Biden) the only way to win is not to play the game.