Ok, but you haven’t explained _why_ this would be inappropriate. If there’s no other way to contact sb, I’ll reach out with a comment where I can. I did this on twitter once. Worst that can happen is that I get no answer, but I don’t see any creepiness.

I suppose most people on HN don’t include a public address in their profile because it’s not required (not even your email is required), not because they don’t want any direct interaction.