Sure, and I didn’t argue for or against the use of that term. The legal definition of theft varies by jurisdiction, but is not necessarily limited to physical objects (e.g. services). I have no idea whether it’s appropriate in this case (I’m not a lawyer), but feels more like copyright infringement.
Control is a part of ownership. If you don't control how something is used and by whom, you don't really own it. So either using it in unauthorized ways is in a manner theft, or Apple's "ownership" is not real ownership. I'm not sure what the solution is, but IP is a tricky concept no matter your position.
It has nothing to do with actually preventing all infringement, but instead seeking enforcement in at least some cases. If a copyright owner is aware of substantial infringement and chooses not to pursue (or license) they may lose their copyright through genericization or other means.
(Caveat: I’m not a lawyer, but I learned broadly the above from an IP lawyer.)