Nobody is forcing you to sell to iOS, though.

We can go up the whole chain and in the end the root platform are nations. If you want access to citizens in a country you got to go through that nations laws, and nobody is forcing apple to sell iOS in Korea.

That argument does not work when there are only two service providers in town, Apple and Google.

It works precisely because there is an alternative with less onerous rules. It works even better because the alternative provider is BY FAR the larger player.

Apple is a minority player in mobile.

Why do you think Apply reduced their fees for small developers and now allow developers to let their customers know that cheaper payment options are available, they know they are abusing that position so to stave off regulations they did that.