But unless you can demonstrate that it sucks because Apple is doing something which qualifies as restraint-of-trade, which I would suggest is obviously not the case, that doesn't matter.

Theoretical competition is not sufficient to demonstrate absence of a monopoly.

The doctrine that it's your fault if your competitors suck makes no sense. It's weaponized tall-poppy syndrome.

The doctrine is that you can't exercise monopoly power in certain ways. Monopoly power is an empirical question, and does not turn on merely whether it is possible to describe a market in which another product exists, but whether that is a real market in which the products are in fact competitive.

But even if you have monopoly power, if you aren't illegally exercising it, you aren't in trouble. So you aren't punished for being an empirical monopoly.