This has been a common complaint in regards to v4 character Liam Brooks' Face-Heel Turn, in that the transition to Ax-Crazy felt rushed.
Compare The Nostalgia Critic in his last Plot Holeappearance to his state in "The Review Must Go On" a month later. The former is still snarky, but more caring, more mature and finally doing a job he loves. The latter hounds Doug into bringing him back, insults with homophobic slurs, is played uncomfortably evil and apparently his desperate desire to atone in To Boldly Flee was a paradox.
Almost mockingly done with Santa Christ. Pre-Son of the Mask, he was the only purely good member of That Guy with the Glasses and all the psuedo-sociopath reviewers treated him like a Team Dad. He could hold a grudge and there was an end to his patience, but he was proof that canon sues could be comforting. In Critic's reboot however, he's bloodthirsty, stupid, quick to anger, tells Critic he's made to suffer and makes him cry, is friends with the devil and is openly told he has a sadist side.