+1 Richard
I think all of these ideas could have been killed with 1 good focus group or maybe field testing 10-20 devices and see how people use them.
Where does modularity work: Indeed, it works great on cars and bikes. However, these products are already modular, so it is a small expense to standardize and allow 3rd parties to develop individual components.
Where it doesn’t work: When the goal is packaging and cost. We want a cheap phone that is as small, cheap and break-proof as possible. Adding clunky physical interfaces works against these basic goals. Moreover, we all know that processors will be 1.5 times faster with 1.5 times more memory and a 1.5 times higher def. screen in a year. The idea of upgrading just a camera module and not the rest doesn’t make sense within that context.