The Original King, you greatly err when you lump the conservative movement in with the GOP. They are not the same thing.
As to why Prager relentlessly pounds "the left" --- apparently he is intent on goading and irritating people like you.
How else do you explain an apparently intelligent individual (you, maybe Enrique) being reduced to throwing out personal insults rather than defending leftism against Prager's relentless, focused, and spot-on rational arguments.
"The bigger the government, the smaller the citizen." This is just one example of Prager's brilliance.
"... he spends virtually ALL of his time trying to demonize 'the left'." This is just one example of your ad hominem attacks in lieu of any reasoned response.
Thanks for consistently confirming Prager's characterizations of leftism and leftists.