You scroll incorrectly. Quite a strange accusation, right? But you are. If you're still browsing long pages on your iPhone, wipe after wipe, you just waste time. There is a much faster way to get to where you want to be, whether it's on a long webpage, a long conversation in Messages or a multi-page document.
In iOS 13, the scroll bar on the right side of the screen: now interactive. That means that you can actually grab the bar when it is displayed and can drag it up and down at lightning speed. When you have successfully selected the slider, it becomes both larger and haptic feedback. From there you simply scroll in both directions as fast as you want.