This is sort of backwards from an economies-of-scale perspective. In the normal world, shipping your software internationally is something of a cost (like filing VAT in all the countries). And even though Stripe has made it way easier to do billing, a small company still would need some servers to do updates, customer service, etc. These things have a cost in time, people, and development.
For an Epic-sized business these things are somewhat small. These costs go down as a percentage of size, not up. So it's almost as if Apple is saying that "bigness" can only happen as a consequence of being on their platform, which I think most people would disagree with.
The attractive thing here is that it is now in Apple's interest to "grow" a bunch of indie developers into bigger companies.