Misunderstood STIG from the sound of it. The STIG is only applicable to unprivileged users but tends to get applied to all workstations regardless of user privileges. Also I think the .mil STIG GPOs apply it to all workstations regardless of privileges.
The other thing that tends to get overlooked is that AC-12 let’s you set it to whatever the heck you want. Ao you could theoretically set it to 99999 year by policy if you wanted.