It's different because the userspace experience is differnt and incompatible. It's an operating system on its own kind of like how MacOS is Unix based but an OS

It's different because the userspace experience is differnt and incompatible. It's an operating system on its own kind of like how MacOS is Unix based but an OS of its own. This is a "ship of thessius" problem. At what point does the ship become a new ship? When it is no longer recognizable as the old ship.