You get a channel for installing apps, where someone vetoes random apps that want to have access to control your whole computer and potentially steal sensitive data?
>Install some GNU/Linux distro and you can do whatever you want.
And any random app can get total control and steal your data, unless you know how to enable restrictions. I'd rather have restrictions as the default, and for the most naive users who'd follow every app prompt, and then cry about their lost work/private documents/money, no way to bypass them.