Any engineer I've met knows Apple's "security argument" about the App Store and Sandboxing/Isolation are two completely separate things, the problem is most non-technical people believe Apple when they say the App Store keeps them secure.

At this point I don't think it's realistic to expect engineers to solve this problem —Apple would retaliate by booting them from the App Store of burying app reviews in red tape. What's probably needed is legislation that mandates hardware manufactures can't restrict what users are allowed to run on their devices.