I think there are a number of democrats who are unhappy, but won’t necessarily vote for Trump, however they might not be voting Biden either.
The term is disenfranchised.
Historically, Republicans win when Democrats don't turn out to vote. When you look at the past 4 years, its hard to believe the Democrats aren't trying to disenfranchise their voter base.
"You gotta vote come hell or high water" is a Conservative mindset.
You vote for a candidate worth voting for is a Liberal mindset.
Neither Trump nor Biden are worth voting for.
That's when liberals stay home, or go third party.
"Hur dur. Vote for bad man. Hur dur. Bad man is better than worse man. Hur dur."