External display & display scaling support
If you have an M1 or M2powered iPad Air or iPad Pro, there’s a new display scaling option in iPadOS 16 to make better use of your screen space; if you go into Settings > Display & Brightness > Display Zoom, you can select More Space. This reduces the size of on-screen elements such as toolbars and icons so there’s more room for content.
It’s particularly good in Slide Over and Split View.
iPadOS 16 also enables M1 and M2-powered iPads to display a separate desktop in a 16:9 aspect ratio. That’s primarily done through the new Stage Manager feature, but you can also view apps on a second display in Split View or Full Screen. Or at least, you could until the very final beta of iPadOS 16 when Apple pulled the external display support over concern about bugs. We don’t know when it’s coming back.