Human nature. Despite all their bluster, they know they screwed up royally. They were playing a Vegas dice game and it bit them. Why else would they be making fools of themselves all this time later and desperately trying to convince people they were really the right ones when the facts line up against them right down the line?
Eats them like a disease. Too much invested. No way to back down without total loss of face.
So they double, triple and quadruple down. Just like any other liberal would. Look at the history and it’s all there verbatim.
I’m getting better at beating them with quick facts. Often they just run away : )