Regarding different payment method, is this an argument to "open" up App store to allow different payment methods?
Regarding Spotify, that is a case I support Spotify actually 100%.
The "Argument" is one I'll leave for the lawyers. Something about monopolizing and actively preventing competition.
The ideal outcome (From Epic's perspective) is for regulation to force apple to allow for external payment options for in-app purchases. That said, if we abstract ourselves from the numbers for a second (i.e the debate about whether the 30% fee should be reduced) it's actually hard to make an argument as to
why they should be forced to do so
within their own app store.
Apple owns the app store, which in turn has hundreds of millions of customers. Epic wants access to those customers, but doesn't want to pay for it. That doesn't really seem "fair", does it?
If Apple were to open iOS to having other App-stores, that is a sub-ideal outcome for Epic too. They absoultely, 100%
would lose customers this way. Mobile audiences are incredibly fickle, and the more obstructions you put between them and the content (i.e Number of clicks) the more likely they are to bail out. Having to download a new app store, get the fortnite app, enter their billing details again etc. There's a not-insignificant number of users who simply just wouldn't be bothered to do that. Look at how their standalone android experiment went. Eventually they caved and just went with the Play store.