Because the people with that holier than thou attitude believe that if they just convince enough people, their socialist/progressive third party that gets one vote every election will definitely overtake both Dems and Republicans in a total landslide, and will immediately stop the genocide in Palestine and the war in Ukraine once they’re in. Or they’re a tankie accelerationist and want trump to win because they think it will lead to a revolution and their perfect political utopia will be in place in mere weeks. They’d just rather die of old age, suffering in a corrupt and polluted fascist hell decades after all their friends were culled, than ever admit that they are wrong or ever accept they will never live to see their desired future.

Edit: I realize I sound super rude and aggressive in the last sentence, sorry. I say they’ll never live to see it because something like eliminating capitalism is an extreme long term goal. It can’t happen overnight, or in a single geneation. It’s too deeply engrained in the entire operation of the world as it stands. It has to be pruned back until it can be removed. It’s like that one phrase, something like men plant trees in whose shade they’ll never sit, or something like that. I don’t think I’ll live to see it either, but I would love to. I’d definitely prefer a socialist society, capitalism has been the cause of all my life’s traumas. But you just can’t get the world to change that fast.