You are wrong, but it's okay because it's simply not common knowledge.
It's like how kids these days mistakenly think Halo pioneered the FPS game genre.
Apple didn't take the UI design from Xerox, only the idea of using a graphical UI. Much of the things we take for granted like direct manipulation of windows, drag & drop, typed-clipboards, and stuff didn't exist in the Xerox Alto. A description of how to move a window on the Xerox is here :
http://www.mackido.com/Interface/ui_history.html
Besides, Xerox was paid using pre-IPO Apple stock as part of the agreement. So the Mac UI design was definitely not stolen nor copied.
While most people assume iOS mostly copied Android's notification menu, they don't realize that Android's notifications menu is mostly a copy of the Windows Mobile home screens. These started in about 1999, and were most likely inspired by 3rd party backdrop applications for the Apple Newton from around 1996. If anybody were to get credit for the notifications UI of iOS and Android, it'd be those long forgotten developers.
The underlying architecture of Android's push notification system is actually a ripoff of iOS'. But since most people arn't developers, they wouldn't know that. (in short, c2dm duplicates iOS' push notification system)