This slightly oversimplifies the situation, as Apple's policy is pretty clearly anti-competitive and, more importantly, anti-developer. As a developer, you have to bump your prices because of the Apple tax.
(And even as a consumer, prices are pushed up. Let's say you want to sell X for $10; too bad: you now have to sell it for $12 if you sell it in your Apple app to make up the difference. The consumer obviously eats that premium.)
I figure you probably see this very clearly, but the problem is that a lot of people don't see it that way, and the law doesn't. Clarifying what is anti-competitive in your view, and crucially what other economic and competition trade-offs you're willing to make to realize that rule, is what will really move the conversation forward.
Sure it is. I'm an app dev and I charge less on the web (via Stripe) than I do on the app stores. I actually have to charge 1 / (1 - 0.30) ≈ 43% more to get the same amount of sales on the app stores as I can do on the web. The 30% is an arbitrary tax that causes the consumer to suffer.