For the vast majority of developers of iOS apps the specifics of how their data is stored and backed up do not matter. If they were not forced by Apple to adopt this set of constraints they would make decisions on a whim, it would lead to less freedom for user, because where there is uniformity, there is a power to abstract, there is a freedom to not micromanage.

Circumventing design decicions is hard. Learning the specifics of particular design is hard practically in the same way. Hacking in an intentionally prohibitive environment is not much different from hacking in an overtly permissive environment — there's a pile of poorly undocumented design decisions which you have to grock before you get anywhere in this system.

So the actual difference it political. I won't argue that preventing little Joe to write the coolest Doom clone ever by requiring all software to be cryptographically signed before running it on a particular game console is somehow more evil than forcing him to spend years learning the ropes and working late hours in QA.

But I believe that imposing certain constrains on people willing to build on your platform is a good thing, because the resulting uniformity gives the platform more leverage. Whethere the constraints are technical or political /in origin/ is irrelevant.