I hate infinite scroll. How do you track where you were with infinite scroll? On mobile when rss is smaller infinite websites tend to reset when the web browser clises down, and I have to re scroll half an hour to get to where I were. I had so much bad experience with infinite scroll that I want to curse that whoever invented inf scroll is a P, M and I.
How do you track where you were in paginated HN? Ranking changes between reading a thread and returning to the page and links often swap between pages.
Most of those websites I use can sort by timestamp and ranks don't change very often. But if the ranks change then yes there is no way to track, but as long as there is something to rank for (popularity is not a good rank)