This boils down to: Democrats didn’t provide a good enough alternative.

Which I will completely accept as true. They didn’t.

From here, there are two branching paths. Did the Democrats put up someone who was actually worse than Trump? As in, are we better off than if the November election had gone the other way? Or did the Democrats have a better candidate who just wasn’t better enough to win? (Fully understanding that this is a very subjective question.)

It’s my firm opinion that it’s the second one. Harris would have been a better President. (So would Jeb! Bush, Mitt Romney, the festering corpse of Richard Nixon, or a frog snatched out of the Tidal Basin.) In which case, giving Democrats any blame for the outcome requires the people who voted for the actual winner to have no agency. They were presented with a choice and they selected the worse one. That’s entirely on them.