I agree it was a high point for UI/UX logic. The filesystem was part of the OS experience and it generally made sense with little magic going on.
I have wondered in the years since whether the newer abstractions and UI patterns we find in MacOS and Windows are actually necessary. These days both OSes are trying to be tablet friendly, trying to discourage user-installed/curated software, and trying to promote bundled cloud services, so it's not even clear to me whether the MacOS 9 abstractions are really the correct ones anymore, as evidenced by the many problems with cloud backed file explorer interfaces, synchronization, etc.
I have wondered in the years since whether the newer abstractions and UI patterns we find in MacOS and Windows are actually necessary. These days both OSes are trying to be tablet friendly, trying to discourage user-installed/curated software, and trying to promote bundled cloud services, so it's not even clear to me whether the MacOS 9 abstractions are really the correct ones anymore, as evidenced by the many problems with cloud backed file explorer interfaces, synchronization, etc.