Additionally, I personally would argue that from a OMG UNIX has conquered the world perspective that Android == Linux as little as Mac OS X == NetBSD since all the parts that people care about are derivative or proprietary.
That isn't true of Android. Sure, if you're writing in Java the *nix-ness is all abstracted away behind the JVM, but if you choose to write native code, you find yourself right back in Linux-land. There are some oddities, of course, like the assignment of UIDs to apps, rather than users. And starting with Lollipop, SELinux is used to block app native code access to many parts of the system (e.g. you can't go looking around in /proc to find out what else is running). But it's definitely still Linux.
It's not true of OS X, either. Again, there are lots of new APIs layered on top, but it's still very clearly Unix. Maybe you meant iOS, not OS X. In that case, I don't know if you're right or not because I've never worked in iOS.