I can also see the argument that for users that discover an app through the App store, they must pay the platform/acquisition costs. But I agree a lifetime 15% is unfair.

Best case scenario is

1) Apple switches their platform monetization to a more direct model where you pay to advertise your app in the App store. This will get tricky because their "Top apps" list still serve as advertising but you can't just remove an app from there because it refuses to pay.

2) Apple removes the restrictions against advertising alternative payment/subscription methods