It seems like he just makes these broad critical statements then pisses off to continue to do nothing.
I wouldn’t even say he’s accomplished great things. He’s accomplished some decent things.
He’s released two games which barely qualify as games. They’re more like puzzles. You don’t need to play them ever again after you finish the first time. Braid is ok. And the Witness is just Flow. And then after that he’s been working on a programming language for the past decade which he hasn’t released to the public because “it’s not finished”.
He got lucky and made his nut and ever since then has thought of himself as way more talented than he is.