I imagine it's because someone commented on it so it shows activity. Dunno how the first commenter found it though. Probably just scrolled all the way back lol.
No you're thinking of 'active', which surfaces posts with recent comments. Just scroll a bit on 'hot' and you'll see it dredges up some old posts, even without recent comments
My instance says 1 year and it doesn’t show in hot for me but shows in active. kbin.social.
