This feature uses an iPad with USB-C. The USB-C is connected to a docking station with a monitor Or just directly to a monitor. The iPad does not allow multiple desktops. It does allow a single monitor but only to show a limited number of apps, namely apps that have second monitor output requirements and feature support.

My biggest pet peeve with Apple using USB-C is this very incompatibility. It made super duper sense to allow docking station capabilities. It would have been well within the capability of the CPU and GPU. And it would have been a killer feature. Possibly even killing the need for macbooks, but definitely killing the idea of laptops.