The fact he's being actively discussed in a thread about books that changed one's life, and your only criticism of the man is an ad hominem, would suggest that he's still very relevant.
I don't care about Peterson. I don't have time to study every intellectual's work. The signals I continually get about Peterson are that he's a hypocritical conservative sexist. Hypocritical in the sense that he presumes to have the answers for life, while landing in a coma due to drug abuse.
Ad hominems are relevant when the person's work involves telling people how to be.