Anyone who uses eww on pages with large images or org documents with large images should check out ultra-scroll. It makes it so that large images in a buffer can be scrolled smoothly (without the jank).
https://github.com/jdtsmith/ultra-scroll
Attached is a video demonstration of me scrolling down a web page with a lot of images in eww. This was the URL if anyone wants to try it themselves.
https://www.realestate-tokyo.com/rent/monthly-apartments-matsuri-technologies/