Software similarity and market positioning don't really come into consideration once the role of gatekeeper has been established.
They had valid reasons for it.
There are no rules that are governing what is or isn't a gatekeeper. It's just whatever EC decides that day.
b) EC never said that iPads and iPhones are the same platform.
I'm just using the CJEU as an illustration that Apple themselves doesn't believe in the “arbitrary rules” narrative as they aren't even fighting in court.
Also, you're trying to use the “bureaucrates” card here, but Apple executives are bureaucrates too, and Apple's management of sanctions and their habits of shutting down user accounts without recourse shows that their own bureaucracy is closer to the one from authoritarian regimes than anything else.