If you want to talk about going from Reddit to Lemmy, probably lack of infinite scrolling, so I went ahead and made a Firefox addon called Lemmy Infinite Scroller. It's 11 lines of code. It's literally an addEventListener for the scroll event. Apparently it can take up to 3 weeks for it to be approved and end up in the Firefox Add-ons store, so I won't link it here, but it's coming.

edit: A few hours later, it's up to 40 lines of code because of handling race conditions. It should work well under normal use now but if people scroll too fast it could cause problems loading two pages ahead instead of one. It's obviously not ideal compared to an official implementation but it's something at least, unless it gets officially implemented in Lemmy before my add-on gets approved. lol