To hop on this train: people like you and I love customizing our devices and tailoring our experiences to exactly what we'd like, and that's completely fine. To a lot of people, though, their mobile device is just a tool—a tool that they can use to do other things. In that usecase, the phone needs to work as simply and reliably as possible, and by reducing the amount of things that can go wrong (live wallpapers draining the phone's battery and sketchy application launchers come to mind) the more approachable that system is.

My take is this: computers (especially phones) are like cars: some people love to tinker with them and take on a project car that they tweak to their liking, but most people need a reliable and inexpensive car that can get them to and from the grocery store.