It used to be pressure sensitive, which made it much faster to respond.

https://en.wikipedia.org/wiki/Force_Touch

> Haptic Touch is a feature on the iPhone XR (but not the iPhone XS) and later iPhone models replacing 3D Touch. The touchscreen, which no longer has a pressure sensitive layer, distinguishes between a tap and a long-press using a timed delay to activate certain 3D Touch features (only ones for elements that do not have an action assigned to long press). This feature was added to the iPhone SE (1st generation) with the iOS 13 update and to any iPad capable of running iPadOS 13. As of watchOS 7, only Haptic Touch is recognized, and Force Touch is discontinued on all subsequent Apple Watches.