Your whole statement sums up nicely why the Dems CAN blame the left: you “will not be voting for Biden”

Ok. I mean you blamed me anyway even when I did vote for you, so much of a muchness really. Maybe you should try blaming those moderate fascists who you dumped the left to try and court for not voting for you.

by finding a way to add at least a third viable party, using some version of Ranked Choice Voting

That would require one of the two parties to feel like they were losing enough votes to third parties to actually implement it.