This brand of laissez-faire sentimentalism is very predictable, but it is neither here nor there.

> unless you believe that giving unfair advantages to Apple competitors is acceptable by any standards, and that this would lead to a more efficient market.

Given that Apple's control of its platform comes with forcing of 30% fees on its competitors (such as ProtonMail, the OP), it would be less giving advantages to other competitors, than refusing unfair advantages that Apple itself has exploited and enjoyed under the current state of affairs.

> Apple made its brand and has a loyal customer base due to the quality of the products it delivers, therefore it's providing what the market wants.

Then it should rest its laurels on the quality of its products and not on restrictive anti-competitive behavior levied upon its competitors. After all the App Store would be nothing without 3rd party developers, and the world in which Steve Jobs had chosen to never open up the platform to such developers would be a much barer one indeed.