> Why is hardware relevant?
Because it's the part that people should own after they bought it.
You can play Fortnite without buying anything on the Epic store.
You can't use an iPhone without being forced by Apple to use the device the way they want.
Many probably like it that way, that's not the point, the point is that if Safari is the root of many exploit for iOS (https://twitter.com/Zerodium/status/1260541578747064326) users cannot disable it and replace it with something else, something more secure
That completely hinder the free (as in freedom) utilization of the device
> If Epic sold a "Fortnite tablet" would this somehow change the legality of Epic's monopoly on selling digital items in Fortnite?
Of course it would!
It would be a monopoly nonetheless
Even though a table that can only play Fortnite cannot clearly be classified as general computing platform.
But it would probably be based on Android, being iOS not available for third parties, and allow sideloading.
The same point could be made about Amazon and the Kindle, but Amazon allows self publishing and direct sell for free.