It's more the Google approach to the ecosystem than it is the Apple approach, though I don't believe the OS is open-source.
Meta accounts only require an email address. There is no real name requirement, which they explicitly state in their help page[1] so this isn't a violation of the TOS.
[1] https://www.meta.com/help/accounts/set-up-meta-account/, see "Setting up your Meta account with email" section.
Eh. No.
VR headsets that don't contain their own processing on the other hand do in fact work like a normal monitor. Usually they'll go in to a "direct mode" that does not appear as a monitor when their drivers are installed for both performance and convenience reasons, but they can be configured to just appear as yet another monitor.
Before these "drivers" had to be signed it was common for various graphics tweak tools to provide a method for building your own custom INF to "overclock" a monitor that only officially supported 60 Hz or whatever.