It's not out of the ordinary for folks on HN to discuss the general subject of a topic and not the exact contents of TFA. The article tends to just be a catalyst for discussions.

It is kinda silly to read comments that do what you mention at the end (have a seemingly novel idea to fix the issue at hand and their solution is the one from TFA). That's just embarrassing.

But I feel like the rest of the discussions are fair game.