You cannot, the behaviour is correct, Account is a child entity of the User entity. You can use another field directly from account if you don’t want to use the Name attribute – for example Full Name.
To be clear, User.Name is an Account attribute, but it’s inherited and belonging to the user table database-wise.
Hope this helps
Simply put, you can't really. And at the very least you probably don't want to.
System.User is the generalization of Administration.Account. You can read up some more about inheritance here: https://www.javatpoint.com/inheritance-in-java
Which explains why you're still seeing those attributes when you use the Account entity.
But if you're simply looking to show a different attribute in the reference selector (such as the Account's Fullname) you can simply set your reference selector to that by double clicking on the reference selector en selecting which attribute it should show.
Ok I was trying to follow the advice of another post that said to use “Account” entity instead of “System.User” so that I could see my user names in the drop-down for assigning. … I guess I’ll have to find another way because System.User is not showing the values (for reasons I understand that were mentioned in a separate post). My best option is to grant permission to see the user names?