This popular gesture is useful because it allows you to make quick edits without having to reach up and tap the display. However, in its latest crop of devices, Apple has replaced 3D Touch with Haptic Touch, and the way the virtual trackpad activates has changed slightly.
On iPhone 11, iPhone 11 Pro, and iPhone 11 Pro Max, you have to press and hold on the spacebar to bring up the trackpad. In other words, pressing just anywhere on the keyboard no longer works.
It's a small adjustment, but it's worth highlighting in case you tried to activate the virtual trackpad on your new iPhone in the traditional way and wondered why it wasn't working. Note that the gesture functions similarly on all Apple devices that lack 3D Touch, including the iPhone XR and all models of iPad.