What about the people like you saying Apple has no place in between 3rd party devs and the end user? You literally said he couldn't have it? From your first post if you had your druthers Apple would be slapped harder and harder until they disband the App Store.
If the seller is voluntarily working together with Apple (i.e. purposefully selling the software through their store) that is obviously fine. The whole point of the DMA is we should not be forced to.