Will abstaining leftists be willing to offer a peace branch and vote for an anti-fascist candidate, even one that disagrees with their wider views,

You mean just like we have for decades now? Yeah, we might just do that. It sure as fuck isn’t going to be the neoliberals who can’t even bring themselves to endorse the Democratic candidate for NY mayor.

Abstaining leftists didn’t change the outcome, apathetic Americans did. And why are Americans apathetic? One look at the Democratic establishment makes that crystal clear.