Evolution of authentication-based navigation

Consider the case where an unauthenticated user sees a main navigation with a few items:

In the old days, someone with admin privileges might log in and simply see additional items exclusive to their role:

In some systems, all of those items would be dumped into an "Admin" menu.

It seems this isn't what is done anymore - it obviously creates a confusing experience for a user who is inadvertently in an unauthenticated state and doesn't recognize it.

What are better alternatives to role-based or authentication-based items in the same menu? Adding secondary/utility menus seems to be a popular solution, but even that seems like a dated pattern. Are admins now taken to their own highly differentiated "admin experience", and is this practical in most cases? What if the admin only needs access to one additional function, such as managing users - is it worth creating a wholly unique experience for that user?