I don't know the guy, what's wrong with what he wrote?
I'm subscribed to his substack because he's curmudgeonly and it's funny, and he occasionally makes good points, but he's constantly beating the same anti-hype drum. He might not get any particular facts wrong but you can count on him only focusing on the facts that let him continue to show AI through that same anti-hype lense.
Gary Marcus has made himself the most prominent proponent of "deep learning is a parlor trick and cannot create real AI" (note: deep learning, not just LLMs), which he has been saying almost unmodified from before LLMs even existed to now.
Though I think he might have stopped setting specific concrete goalposts to move, sometime between when I last checked in on him and now. After (often almost instantly) losing a couple dozen consecutive rounds of "LLMs/deep learning fundamentally cannot/will never", while never acknowledging any of it.