I think you made his point for him. Your contention is that MSNBC is not extremely left left wing. His contention is that the NRA and PragerU are as extremely right wing to the same degree that MSNBC is extremely left wing. So if MSNBC is not extremely left wing, then I think GP's point is the the NRA and PragerU are perhaps not so extremely right wing as GGP implied

Though I think I made it clear that MSNBC is not extreme left-wing, I didn't make it clear that their juxtaposing of MSNBC's centre-left political platform with the platform of PragerU is wrong, and I perhaps initially misconstrued their comment.

PragerU has hardline-conservative positions on climate-change, abortion, religion, immigration, and economics that are certainly more deserving of being called extreme than MSNBC is deserving of being called left.