Reading his post was like a gut punch, and I didn't even know the guy. It breaks your heart to hear someone speak with certainty about their own demise, and to face it with such grace and clarity makes it all the more heart-wrenching. It sounds like he was with his family in his final moments, and I hope he wasn't in much pain. Rest in peace.
Your comment reminds me about Polish movie "Life as a Fatal Sexually Transmitted Disease", which is a story of a doctor dying from cancer. Some variations of this title were semi-popular in Poland in early 2000s.
About 160,000 people die each day on this planet. It’s probably safe to assume that a good number of them are facing it with grace and clarity. The fact that many aren’t able to, for one reason or another, is maybe more heart-breaking, in a way.
I just relatively recently found his posts through HN. Even though I've only read something like 5-8 posts, I quickly became "attached", for lack of a better word, as I truly enjoyed the writing and openness. It brought me closer to that kind of situation, and the people in it, than I've (yet) ever been. I wish them all the best.