There's no legitimate reason for job restrictions on glamour to still be a thing; there wasn't even one when the system was first implemented. Immersion is a poor argument when so many non-locked glamours fly in the face of it entirely.

I'm even okay with unlocking artifact attire. I never get to wear it since I play multiple jobs in a single role, making it a forever non-option.

As long as you're high enough level to wear it on the job it normally requires, you should be able to wear it on anything else. It's really not that complicated.