Maybe as to give at the very least a tangible reason as to why the employee would be prohibited to drive?

Saying only “you can’t drive shit” is batshit insane. Saying “you have no license so you can’t drive shit” has some reasoning to it. That’s how I read the extract from op ( and hopefully what they meant ) . Best guess is they sponsored an employee in the past who went crazy without a license and maybe it fell back on them.

Saying you ain’t Japanese so you ain’t getting a Japanese license so you can’t drive shit” is insane though as you can still get one through conversion, international license or simply passing the exam, and op should clarify that with them.