Im not telling to vote for Trump. I'm not even telling you to not vote for Biden. I'm telling you to fucking ask for something in exchange for the vote.
There's a separate argument about what the value democracy is if it can't be expected not to support genocide, but I'm not even pressing that issue.
Saying you aren't going to vote if Biden doesn't see reason doesn't put Trump in the white house, it puts pressure on Biden. What you actually do on election day is different, but campaigning for Biden despite his genocidal complicity is so far from activism that it's borderline complicit in the genocide in itself.