That's exactly it. Instead of copying Apple's intent, competitors instead copy the result without ever giving a moment to consider the original motivation.

This reminds me of a post by Tog or someone similarly luminary. He explained that the Mac OS submenu behavior arose from multiple iterations, refining until everything worked easily. A big part of that was letting the user move their pointer at an angle into the next submenu region. A Fitts' law consideration -- this didn't require the user to be too methodical in their movements through the menus.

Then, when Microsoft borrowed the UI, getting into submenus required the user to exactingly follow the path of the currently-highlighted menu item in order to traverse into the next. Breathe the wrong way and your whole drill-down progress just disappears. Microsoft's solution? Insert a brief delay as you hover over a drillable menu option.

Result without intent.

As it happens, this reminds me of the UI for Windows Phone 7. It's like a suit said, "Hey, go design me something that looks really modern. And hip. With sans serif fonts. Apple uses those right? They're really hip."

And we end up with a UI that looks more like a magazine layout than a tool for using your phone.