Phantom Linux is in no way associated to other distributions or operating systems.
Phantom Linux is just Arch Linux, themed and configured for an out of the box experience.
Themes come from upstream published open source projects publicly available, mostly from Github. We are not aware of any copyright or trademark infringement. Any complaint should be directed upstream and will be subsequently incorporated in Phantom Linux.
Concerning the names of WindowsX, MacX, and LinuX, the reason of the “X” is because Phantom Linux uses the “X” (or Xorg) system. They are specifically not connected to Microsoft Windows™ or Apple's Mac™.
Logos and icons are considered open source as explained on Wikipedia:
Those images consists only of simple geometric shapes or text. They do not meet the threshold of originality needed for copyright protection, and are therefore in the public domain.
We use themes inspired by other operating systems only for the ease of the user. However, if the user likes the original, he is encouraged to get original Microsoft and Apple products.