I agree, infinite scroll is okay for threads (I too had set the old site to display 100 posts per page), especially with the scroll-o-meter thingy on the right.
But it is a darned nuisance in other contexts. For instance, if I want to see the first post made by my other self, @tee_eff_em, on the old site, I can display all 5.6K posts created, but I would infinitely scroll an awfully long time to get to the bottom of the page. Maybe it will be better when search is functional?
(eta: Especially annoying due to the plethora of titles like “Question”, “Did I Commit a Sin?”, “Can Someone Help Me?”, et cetera.)