Does that mean I have to pay you royalties for thinking about it or mentioning it?
Yes, if HN were to post copyrighted work that only they could spread, then you would be liable. In the same trend, any patents that HN comments share should not be redistributed/sold by you.
Chatgpt circumvents copyright law in a way that is hard to detect. How many sentences of moby dick does it take to prove chatgpt is plagiarising other peoples protected works?