AmigaOS and the like are used because some people like to mess around more with the inner workings of the OS, or at least understand what it does in the background in some level.
Windows are OSes for people that don't understand a {bleep} abour computers. They abstract the user completely and make all the decisions for him.
In that respect I don't think AmigaOS should EVER become a general desktop OS. People that like computers for what are, normally disklike windows one way or another...
