Not really. Two reasons, once developers have another option they'll move off the App Store (look at the Mac App Store) and the peace-of-mind for users diminishes the responsibility of vetting an app and securing your phone now falls to the users.
It also isn't as simple going the other direction. Remember, Epic also sued Google because even though Android is "open" they have put up so many barriers to side-loading apps outside the Play Store to solve their inherent platform security issues. Yes, there is economic incentive for Apple and Google to force/encourage/lock you to their store, but saying that's the only reason is purposely myopic.
There are compromises but there aren't easy, obvious answers. IMO, of all the complaints about the App Store, Epic's is the most disingenuous and hampers more legit criticisms.