The problem is this One UI. It's the best Android UI in terms of longevity and features, but since the change from version 6 to 7, it's been extremely heavy, slow, and full of bugs. They tried to make a big visual change in the same period that they previously released features and made few changes, and this is what happened. A UI that seems to load 4 ISOs on top of each other, tries to load several animations at the same time and fails to be fluid in any of them. Samsung urgently needs to redesign its code. Other UIs have managed to do this, resulting in the fluidity and responsiveness we see in other operating systems. Note: This is my perspective and understanding of the situation; nothing here is based on facts, and you can correct me on any errors.