At some point, one of the candidates for the democratic nomination will secure/win that nomination, and he/she will likely run against Donald Trump. If part of the democratic base stays home like the Bernie Bros did last year, there's a good chance we have 4 more years of the same. I am not sure much could be worse than that.
It's why though I have my reasons for wanting Beto to be that candidate, I say nothing about the flaws of Harris, Warren, Biden, Booker, Sanders, Kloubacher, etc etc... because ONE of them will ultimately be MY candidate.
If the Dems lose this election, we deserve what we get. Fool me once, shame on you (Republicans), fool me twice, shame on me (Democrats).