iTunes was released for Windows in 2003, so it was available for free on all major platforms. The iPhone was released in 2007. If iTunes had only been available on Macs, it would have been perfectly reasonable to consider the iPhone a "Mac accessory", but it wasn't, so it isn't.
Nah, that’s a different sense of the word “accessory”. Trapped in the ecosystem is one thing. But the question here is whether it’s a substantial, standalone product.
