I tend to think the issue is, in fact, security. If Apple (or Google or anyone) had a truly secure phone, then there should be no need for curation of apps. But our devices are full of zero-day exploits and dangerous "private APIs." I think the next generation (as in 20 years from today) of devices will embrace a secure-by-default mindset and thus not make users choose between the nanny-state and the wild west.