This is not true. Apple can absolutely (but probably won't, as unfortunate as that is - and I hope I'm wrong on this) build APIs for hooking into the views used

This is not true. Apple can absolutely (but probably won't, as unfortunate as that is - and I hope I'm wrong on this) build APIs for hooking into the views used in the current system, while the actual transactions happen outside of it. They can't guarantee that the data shown is what is actually being charged though, which is why they probably won't do that.