Disagree, because her approvals are even lower than hers, and she has shown no great aptitude for climbing out of the hole. She may be fine, even competent, but she would not be the chosen one.

I think that's wrong. If Biden chooses to withdraw from the race (again, exceptionally unlikely), then he's probably going to choose the successor. Nearly all those delegates are Biden loyalists, after all. He's unlikely to pass over his Veep.

After all, it's going to be a monumental task to get him to look in the mirror and admit that he made a catastrophic mistake in choosing to run again; it would be another massive lift to get him to admit that he made another catastrophic mistake in choosing his Veep. Or to convince him to compound his dubious 2024 legacy (the first person to clinch a nomination but quit because they couldn't hack it?) by passing over his own #2, who happens to be the first black and the first woman Vice President in history?

This is not about “being nice to Joe” or even to Harris, it’s about what’s most likely to carry the election.

That would be true if the party was making this decision. Or some discrete subset of the party. But it's Joe that will get to decide whether he's the nominee, and whether he'll pick Harris as a successor if he chooses to step aside. I think there's virtually no chance that he'd both step aside and decline to use his influence over the delegates to pick who he wants to be the nominee. I think it's pretty unlikely he'll even agree that Harris would give the Democrats a better chance of winning, but I think it's even more unlikely he'd agree that an open convention gives them a better chance.