I don’t think locking down slashes support calls because you will now receive support requests anytime someone wants to install something and actually have a good business reason to do so.

Consider the ones you don't get: ones where PCs have to be wiped from customization gone wrong, politics and productivity police calls - "Why is Bob gaming?", "Why is Alice on Discord?".

It's about the transition from artisanal hand-configuration to mass-produced fleet standards, and diverting exceptional behavior and customizations somewhere else.