"Progressives should not make the same mistake that Ernst Thälmann made in 1932. The leader of the German Communist Party, Thälmann saw mainstream liberals as his enemies, and so the center and left never joined forces against the Nazis. Thälmann famously said that ‘some Nazi trees must not be allowed to overshadow a forest’ of social democrats, whom he sneeringly called ‘social fascists.’
After Adolf Hitler gained power in 1933, Thälmann was arrested. He was shot on Hitler’s orders in Buchenwald concentration camp in 1944."
The point though is that ranked choice allows you all the benefits of 3rd parties without the downsides.
One can just as easily argue that that is the point of primaries in the US and other countries. You get a wide range of left and right leaning candidates and you downselect based on who the majority wants as well as general election theory to handle moderates.
And… the end result is that people get incredibly pissy when their candidate doesn’t win and disenfranchise themselves. Theoretically, a very strict ranked choice model that requires ALL candidates to be ranked could help with that but you still get into the realm of “protest votes”. See: People who refused to vote for Biden because he had shit stances on genocide and who would have given trump, who is openly genocidal, the win.
The reality is that we need to actually educate people on how governments work to undo decades of “haw haw, douche or a turd sandwich” levels of narrative. But we also need the politicians to actually unite against common threats. The fascists already understand that. But the Left continues to infight at every opportunity.