Which has the exact same electoral effect as voting for Trump. There is no difference electorally than voting for Trump vs. abstaining if it is someone would otherwise vote for the Democratic option. Both are a net +1 for Trump's margin in whatever state the vote would be for.
Does our two party electoral college system suck? Yeah, but that is our system so that vote works out to be a +1 for Trump's margins regardless if its filling in the Trump bubble or just not filling in the bubble at all.
I didn't want Bernie to win, but I would have eagerly voted for him in November because the fate of the world depends on stopping Trump and putting in place a competent cabinet and working government. I'd have voted Bernie even though I didn't want him to win the nomination even if he had a similar accusation made against him.
Because for me, it isn't about what I want. It is about saving my country. Biden, Bernie, Bloomberg, Warren, Buttigieg, etc. Nothing would change for me in November. I'd be there. I'd walk over hot coal for any of them. I want to save my country from this vile wannabe dictator.