Truth be told, I find nothing wrong with the central App Store security model, merely that the status quo is insufficient. They should either ramp up enforcement on the store drastically, and/or open up the platform to third party stores, and thus competition, for other stores to attempt better ways at enforcing security and user privacy.
I do not view opening up the platform to third party stores or sideloading to be an excessive security risk, because having studied iOS's security model, it seems to be reasonably hardened (at least compared to Android) and I believe that Apple can manage the existence of other app sources well enough to prevent them from becoming significant malware vectors. The fact that those malware links are neither ransomware nor botnets proves how inherently secure iOS is, and thus protections are built into the operating system level, thus making the existence of third party stores irrelevant to its security.
> They should either ramp up enforcement on the store drastically,
This, I agree with.
> and/or open up the platform to third party stores, and thus competition
This I disagree with. As stated elsewhere, I simply don’t think security will be the basis for such competition because it relies on end users to be able to make that a priority over just running the apps they want.
I think if Apple is unable to maintain the security of the platform, competition is the answer, but in the form of other platforms, not Apple being forced to allow alternative stores.
Fortunately iOS users don’t have those problems because of the security model that you are so quick to dismiss.