I agree that we shouldn't shame someone in that situation.
But the counterfactual still exists -- if Biden loses, that means Trump wins. And under Trump, things will be far worse. If we're calling Biden genocidal for taking a cynical and cowardly approach to the conflict, then I am not even sure what word can possibly be extreme enough to describe the guy who actively wants all Muslims and Arabs dead.
I fundamentally disagree with the view that your vote is some signal of deep personal convictions. Voting should always be strategic. The more strategic, the better. That's also why how you vote in the presidential election as a resident of California can be VERY different from how you vote as a resident of Georgia. I'd love to see a significant number of people in places like New York and Colorado voting third party in protest -- because it's not going to be enough to influence outcomes in that race, but may have a real and positive effect on future politics.
I just want everyone to think very, very carefully about what the counterfactuals are. In all things.