I wish journalists wouldn't refer to Apple's app store cut as "tax" ; it's a service fee. That is the price Apple charges for providing payment-related services on its platform. It is not a tax.
Is my income tax a price the government charges for providing roads, schools, and protection? Just because there are services rendered doesn't mean it's not a tax. There is no opt out, and price is a function of earnings rather than value added.
Taxes imposed by a government are compulsory.
Words still have meaning and using tax to refer to Apple's fees is completely incorrect.