Earlier quoted context omitted.
Based on what arguments? If Apple’s cut were 12% and Epic and Microsoft now charged 6%, would you claim “The 12% that Apple charges seems about right IMO” ?
Yep, if someone is able to maintain above market level profits for so long it's usually a sign of monopolistic pricing. That's not necessarily bad, but in Apples case it's just double dipping on their monopolistic position and is clearly a drain on the market with no benefit. They have the same incentives to invest in R&D and support the ecosystem on the insane HW margins alone, I'd be willing to bet their dev budget…
Also, Apple will claim they have a better product that warrants higher margins. Data from independent parties shows that they attract more users willing to pay for apps, and developers aren’t leaving en masse for Android.