I will want a clearly marked difference in brands. One brand can be where the restrictions are associated under a common service. Another brand can be all-you-want-install set of stores.
I have had cases maintaining systems where the common denominator was to reinstall a system.
In the hypothetical scenario where iOS permits active side loading of applications, then there should be, in my opinion, two separate brands. Brand 1: iOS (classic), Brand 2: Generic Brand. Let’s call it Epic mobile brand.
While in principle I want to install any software on any hardware. In practice if an issue comes up on non-iOS brand, let’s call it Epic Mobile OS, the fast solution is to reinstall the OS. I want these to be clearly demarcated , so that I avoid the onslaught of crappy apps in the second category requiring re-installation.
And I am old to consistently reinstall OSes.