I'm not breaking anything. I'm providing information about an alternate service. If you choose to use the IAP, you get the same UX you always did.

So they prefer the UX Apple provides.

With a price of zero they do, but how much is that UX worth to them? How much is it worth to you? I say lets expose it at its true cost and if people want to continue paying that cost then more power to them.

Now if we start adding incentives towards the other method you are pushing them more to what YOU prefer they do.

That's not true at all. Apple is charging 30% for that IAP experience, but right now you have no choice but to pay it. The "incentive" is just "pay a lower price for a lower grade of service", and without that we don't know if Apple are overcharging for the higher grade of service or not.

If, as has been posited, Apple's IAP UX is absolutely worth that 30% to a significant number of consumers, then they'll rationally continue to pay that 30% for that service.

You as a single developer would always be incentivised to take as much money from as many customers - hence dark patterns.

With the 30% discount the developer is in fact making exactly the same money either way, so they don't care which you go with (in fact, they'll make slightly more with the IAP under that scenario, because they'll have to pay processing fees for the out-of-app purchases).

Overtime the trust in the “it just works” erodes as it doesn’t really work well anymore. I don’t think this is something that Apple want to see.

I don't see how. The IAP button is still there. I can also imagine consumers making the decision on whether the 30% is worth it on a case-by-case basis - you might be happy to pay Netflix or Amazon out of app, but maybe for some $2 purchase of magic beans in some throwaway game you'll figure the $0.60c is worth it not to have to stuff around creating some new account on some fly-by-night website.