There might be a small issue here.
In spite of the excitement surrounding Apple’s new Pro Display XDR for the 2019 Mac Pro, a new report from AppleInsider states that the display only supports a 5K resolution, as opposed to the 6K it’s been marketed as supporting on certain machines:
According to Thomas Grove Carter, the Pro Display XDR features a 6K, 6,016 x 3,384 pixel resolution. Carter wrote that the display only achieved a 5K resolution when connected to an iMac Pro.
Per Apple’s product specifications page, Apple has stated that the Pro Display XDR is compatible with a variety of Mac models, including the 2018 15-inch MacBook Pro, which features an MPX Module GPU, the 16-inch MacBook Pro, the 2019 21.5-inch iMac and the 2019 27-inch iMac. Other supported Mac models includes those with Thunderbolt 3 ports as well as hardware paired with the Blackmagic eGPU or Blackmagic eGPU Pro. Apple’s support page describes the setup process for the display, which states that the aforementioned Mac and Blackmagic eGPU setups are able to support the 6K resolution with 10-bit color.
Apple has yet to offer an official statement as to the issue.
Via The Mac Observer, AppleInsider, Pro Display XDR specifications, support.apple.com and @thomasgcarter