He is an entertainer

I’ll preface this by saying I don’t particularly like the direction the channel has gone. He’s sold out big time, as described by many comments above (both literally, by selling the channel to VC, and metaphorically, by selling out whole videos and the integrity of their content to advertisers as the Tom Nicholas video explains). And his ties to grifters like Colin Grey and Philipp Dettmer (of CGP Grey and Kurzgesagt fame) definitely don’t work in his favour.

But that said, I think this comment you made is a bit reductive. He has a PhD in effective science communication. He can legitimately claim expertise in communicating science to the public via YouTube in a way most popsci content cannot. Obviously not the same as doing scientific research himself, but he also doesn’t claim to be doing that.