[Jekyll]

I guess you just summed up the benefit of having a non-specific HN in your last sentence.

Serendipity has led me to find all sorts of wacky stuff here that I would never have found otherwise.

Perhaps they may be some sort of benefit for having a "HN for [insert topic here]" for people to find a narrower information set. Personally, I like it as it is and one can always use the search function to target posts with keywords