Gravis asked my opinion on using a PCB motor with a prism.

In short, it seems possible to spin a prism with this motor but the prism most likely needs to be smaller.
This motor has a diameter of 15 mm,  my prism a diameter of 30 mm. Of course, prism dimension can be changed.
The prism can be placed in a low drag gas like helium. So far Carl seems to focus on torque and speed, an important quality for me is actually planarity. How planar is the rotation? At 5 minute 43, he shows the side ways wobble of his amazing device. This kind of wobble is undesirable and would require a cylinder pair to filter it out. This increases price which kills the low cost advantage of the motor.
Small prisms are desirable for high accuracy applications.

I would try to create a digital twin, this would greatly improve understanding.
Options I see

             - Magpy Lib: should be easy for a quick experiment

            - Pyleecan: geared to motors but does not have example of this exotic geometry

              -      Elmer Fem , can be linked with open foam, probably too advanced and not suited
                                          for exploring the problem