I think you missed a very important issue: memory and CPU resources. Scrolling multiple pages of photos, GIFs and videos without reloading the page can take a significant toll on system resources. Most notably on mobile web browsers, the scrolling animation will skip frames more and more frequently, general responsiveness will suffer, the phone will consume more energy, causing overheat, and eventually the tab or browser may crash if there’s not enough RAM. Always consider how much memory and CPU your page consumes if you’re using infinite scrolling. Test in different devices and use tricks like pausing videos and GIFs when the user scrolls past them.