Operating System Requirements: macOS 10.14-macOS 11 Description: This software provides support for the Sonnet Thunderbolt Pro P2 Card Reader with computers running macOS 10.14 - macOS 11.
IMPORTANT NOTES:
This driver is not compatible with M1 Mac computers.
You need to use the top Thunderbolt ports on the 2019 Mac Pro. (For some odd reason the rear Thunderbolt ports of the 2019 Mac Pro are not compatible with the P2 reader.)