Yeah. Scrolling(amount of scroll per turn of the scroll wheel/swipe on touchpad) has been intentionally slowed down. Another issue is when you scroll fast, the scrolling is stuttery because papers tries to render on the fly when scrolling. There is an open issue to discuss whether this should be the behaviour or not.

But don't worry too much. It was much slower a month ago and yet progress is being made at a great pace and hence I expect it to get better in the near future. Pablo Correa Gomez(the lead dev of Papers) is doing some great work.