I think he thinks HE had to store the information, and if he isn't the one storing it, it's anonymous.

Except, on Android, you can also do it where only google stores the information and he doesn't have to store any. And there are no user name or passwords or accounts involved to listen to specific channels like he claims.

You can collect this information, and you'd be able to write a more custom push service, but it isn't needed at all, but Google and Apple will always know who is getting the messages.