Blackmagic Design has posted Blackmagic eGPU 1.2 Update, which adds support for the Apple Pro Display XDR to the Blackmagic eGPU and Blackmagic eGPU Pro.
Once the update has been installed, you’ll be able to use Apple Pro Display XDR as a computer display when connected to a Mac with Thunderbolt 3 and either a Blackmagic eGPU or eGPU Pro. The eGPUs are the only ones that officially support Apple’s high-end, expensive display.