I see our opinions of Saifedean overlap considerably. I was basing that view on some of the interviews I've heard him give about his books and the fact that every time someone quotes one of "his" economic insights on nostr it's pretty standard Mises/Rothbard stuff.

My understanding of Man, Economy, and State is that Rothbard was initially just trying to make a more accessible version of Human Action. In the process, he found some errors and corrected them, which led to some new insights to write about. He also extended the analysis a bit into some of the libertarian topics he's interested in. Most of the libertarian stuff is in Power and Market, though, which is sometimes treated as a supplement to Man, Economy, and State (and which I didn't think was as good).

For what it's worth, I think Man, Economy, and State is an extraordinary economics treatise. I thought the presentation of many economic principles were much clearer than other writers, while also maintaining technical accuracy.

The reason there haven't been any major serious updates of those books is that they're still considered very good introductions to the Austrian School. More contemporary writers have focused on specific areas to apply the theory to. That leads to occasional updates to the older theory, but nothing that necessitates a new treatise, so far.