I've been making searches across JN and couldn't find this exact issue I'm experiencing.
I work in a School and we have multiple macOS devices which need to have the Fast User Switching enabled and the FUS to be displayed with Full Name in the Menu Bar.
I used a new Configuration Profile with Payload "Login Window"'s Options set correctly:
The problem is that after we scope the devices, the FUS doesn't work as intended.
The option is greyed out into System Preferences, both from "Login Option" under Users & Groups, and Dock and Menu Bar:
I tried to overwrite the preference files as suggested here
The result is that I can't overwrite the preference file because it's protected.
The only way that I found to have the FUS working as intended, is to NOT have a Configuration Profile configured, and set the options manually. But that can be painful with more than 300 devices.
Is anyone experiencing the same? Is this a known issue?