My intuitions are only that, given the incredibly unpopular Republican culture war platform, there's going to be a lot of enthusiasm down ballot, even if there is squeamishness for Biden himself; Dems are positively stronger on labor than any time in recent memory-- UAW and SF probably net Dems big in MI, if anywhere. I think sans Gaza Biden would be looking at a larger margin than last time, and from your helpfully provided numbers above, even that 80k protest vote isn't sufficient to cut into the 2020 margin (those people are not going to vote for Trump).

Again, I think we agree that as long as there's a plausible threat that Biden flubs, there's hope for some concessions; I'm not sure Biden losing is good, but I wish the threat was stronger/more motivating.