That won't work because many people here post anonymously. They have a throwaway account and make a new one now and then to leave no trace to their real identity. Leaving an email address would mean having to maintain a throwaway email in sync with the HN account.
Nowadays that's even harder to do since HN shadowbans new accounts for a while. You write a comment and you are surprised that nobody replies. It's because nobody but yourself can see it.
Which, ironically, contributes to the issue disussed here.
I'm also using a rather new account, let's see if this msg actually is visible now.
Otherwise if someone wants to follow up with you about a comment, there is no way to do so without spamming a public comment reply.
Contact info!