Anything possibly released by Hal would have been part of the protocols we observed today on the bitcoin network  or probably part of the BIPs implementations that was introduced, nothing new aside these that has to go with a newly developed technology without conformity with the blockchain technology, maybe going ore deep on his threads could give more light on that, because it's what i know that without Hal, bitcoin history is never completed.

I don't think it was implemented outright but trusted computing is a thing now, so I think his legacy lived on in spirits. Plus he's a key figure in the cryptocurrency world we're living in today, hard to think that he's not going to cause major impact at least in the younger minds that came upon his post. Most processors right now implement some form of Trusted Computing module or protocol which users can toggle on and off, I'm not really sure if this is usable for the cryptocurrency industry but with the little I have read of it, it's looking promising. In one way or another Hal's dream of bitcoin becoming a massive financial phenomena that changes the lives of millions of people became true. He's a legend and I hope he's in a better place now.