That is true, we dont vote democrat for progress, we vote democrat because republicans want to annihilate us. Voting democrat is just a patch to give us more time to organize. But, yeah, voting for any liberal will move the Overton Window to the right every tims. That is an irrefutable fact. The point of voting democrat is just for it to not move as much as it does with republicans.

We cannot overthrow the bourgeoise by voting at all. But voting does changes the speed in which things detereorate. Republicans are accelerationist in this regard.