I wrote it to you, not them. I thought you will find it useful.
Also I don't expect GP convincing HN users to protest or to reach out older relatives, or whatever would help the 60+ fb users, but my comment convincing HN users to not to do that.
That seems unlikely. It come across more as a passive complaint about the comment. A sort of “Why are you bothering me with this?”. I doubt you believe the other person wasn’t aware of blocking abilities, as you provided no actual assistance in that direction either.
Also I don't expect GP convincing HN users to protest or to reach out older relatives, or whatever would help the 60+ fb users, but my comment convincing HN users to not to do that.