I held my nose as I voted for Biden in the primary, but I don't even recall anybody else being on the ballot. I was elated that he stepped down and endorsed his VP.
Admittedly, it sets a scary precedent, I certainly won't disagree. But setting the implications aside, was it really the wrong choice? Did Biden really fare better than Harris in the general? I certainly don't think he would have. I think Trump's margin of victory would have been even higher against Biden.
Probably not, but does it matter? Biden was also not chosen in anything resembling a democratic way. US political primaries are not democratic.
The general population being presented a choice between two options that were selected by two ultra-partisan entrenched entities is not democracy.
To have a system somewhat resembling democracy you would have to either (1) open primaries to everyone regardless of party registration with no control by partisan organizations over who gets nominated or supported (which would mostly defeat the point of having political parties at all) or (2) have a more proportional system where it is meaningfully possible to create new political parties that gain a nonzero share of representation.