They believe if they don’t vote that the democrats will magically transform all of their policies to communist ideology to capture and extra 0.3% of voters at the expense of losing most of their voter base.

It’s because it’s a deeply religious position for tankies. They aren’t interested in political strategy or, despite their claims, material conditions of society. They have utter disdain for ‘shitlibs’ like socdems and demsocs - the disdain they have for the vast majority of the population, who is even less on their side, is far greater. They have no desire to try and change opinions on the ground. Why would they want to stoop down to the level of sinners reactionaries? No, all they want is for the poors to suffer and the minorities to be exterminated in the hopes that their rapture sorry, proletarian revolution, will trigger because of the end days accelerationism.