Fact is you have two real choices because of how elections work
Fact is if you don't push for the lesser, even going as far as to push people to not vote for them, you are actively pushing for the worse person to win
Fact is the more dems that win, the more power the whole party gets. That means more progressives have real power to change and can sway the more right members of the party.
Fact is anyone pushing "they are the same" and not voting are responsible for the bad caused by the right winning more and more and helping to push their Nazi agenda.