Today, 26/10/21, Apple have issued an update to Mac OS Big Sur. It is Mac OS Big Sur 11.6.1. If you install this update, then you should find that Canon Print Studio Pro will now be working as it should do.
I have copied the Print Studio Pro plugin from Canon's own folder on my PC, then on my PC gone into adobe Photoshop cc 22xx and have gone into the folder "Required" I pasted in the whole Canon folder. I do get an error message telling me my plugin has not installed correct each time I open Photoshop, but it is there, and it works fine wih all my prevous setting still available. It's not perfect, but it works and allows me to print as before. Hope this is of use!!