I think it's to stop the HN equivalent of "doomscrolling" or mindlessly wasting time. If you have to wait then there's time to think, ok should I even be doing this right now?
HN is probably one of the most varied, important bits of my media diet. Then I'll circle back for any discussions I think might be interesting.
Do you also do that thing where you think of an HN headline some weeks later and go "Oh! I think I saw something about that?" then dig through your history, find it, and then read it?
i do this all the time, with websites of all sorts. i really wish the browser would allow me to search the text of all the sites i’ve ever visited (realizing that’s a big ask), as regular internet search (ddg) often doesn’t return the page i dimly (and perhaps incorrectly) remember.
I don't know how else to explain it, but if I can't exactly remember the title, sometimes I remember roughly what it "looked" like. Completely subjective, impossible to implement in a way that would be useful, but that in addition to searching text as you suggested would go a long way toward finding something!