To be fair, its been tried a couple of times to build really customizable machines. It is just more expensive from a manufacturing point of view and the market is never really there. The Treo lost its slot and I seem to remember an attempt by some of the Amiga team to build a PC in a modular way (ended up in a museum somewhere).
The problem has really been the cellphone focus which means "open" = "what carriers want". The lack of a true iPod touch equivalent has hurt the potential of Android.
I really think if you were trying to build and open, customizable, modular platform, it would be competitive with Apple, Microsoft, and RIM. Android really doesn't have a love for an ecosystem of gadgets around it. It is a lone wolf and needs to really have a high speed connector where people could really build cool add-ons that it can plug into. Make it the "I can carry my world" device that can be plugged into other things to get more power / capability.
The funny thing is that the inside of the Mac Pro has so many niceties from a hardware expansion point of view that never really appear on PCs.
To be fair, its been tried a couple of times to build really customizable machines. It is just more expensive from a manufacturing point of view and the market is never really there.
Customizable machines are a billion dollar industry, chances are, you're sitting in front of one right now. It's not a matter of making a customizable machine, we know how to do that. It's a matter of actually allowing the user to customize things, which can be done by allowing core components to be swapped out for alternatives. In this context, the customization doesn't need to be complete/absolute, it just needs to recognize that different users have different needs and work differently. A consumer/home user may find the grid of icons on the iPhone screen to be easy to use, but the business user may want a calendar or email listing on their home screen (interestingly enough, we laugh at the members of both of these groups who end up with a massive grid of icons on their desktops, which is obviously bad for usability ("The link to the website was at the tip of the penis!" -- Sales Guy vs Web Dude). And Android offers the capability for apps to provide this functionality, but Android isn't considered to have Good Design(tm) (or is at least "less" than Apple's design) despite this capability.
Isn't this a rather old trend? As technology becomes more complex, we rely on the creator to make sensible decisions about the interface to allow us to focus primarily on what is relevant to achieving our goal.
Abstraction is the only way technology can become more powerful and more accessible at the same time.
Things aren't better just because they're more configurable, even if customization is a goal. More often options are just varnish because the defaults aren't reasonable. Make the defaults good first and then add configuration and options.
