>But why, is still beyond me.

It's a coping mechanism for psychologically weak people to try and maintain a sense of control in the face of something they are powerless to confront. You will notice conservatives have the same reaction to all existential threats such as pandemics, pollution and climate change: blame the messenger and bury the truth. It makes them feel safer to deny the existence of these things. And by transforming the enemy from an amorphous threat like a virus into a cabal of evil liberals who just need to be removed from power, it gives them an enemy they understand how to fight (because it can be fought through simple violence/force).