And sometimes it "just works", but only if everybody is within the Apple ecosystem. Otherwise, it's just a net exporter of problems. See, for example, SMS message of "Liked an image.", email attachments converted into icloud download links, .DS_STORE files scattered everywhere, and so on. Any time Apple comes up with a new feature that would require improving capabilities at a lower level, Apple instead makes a new layer of abstraction on top. And oh how conveniently, that new layer of abstraction is transparent only to Apple users.