The situation where you can purchase a service for 30% less elsewhere but not on the iPhone is pretty insane. And on top of that, you are not allowed to tell your users how to get a better deal.
Regardless of his reasoning, Apple and some others have too much power.
It's not a "clear alternative" when Apple doesn't even allow you to mention that. There are other reasonable alternatives such as letting developers mention the alternative payment methods as long as they explain what the benefits of Apple payment ecosystem.
I read a lot of people writing comments like "I prefer to go through Apple because of the ease of unsubscription." If the benefits are so clear, why are developers not even allowed to mention the alternative?
Regardless of his reasoning, Apple and some others have too much power.