Frankly, I would assume anyone with one of these must not really have any business existence at all. (emphasis added)
That is a silly statement in its sweepingness. Certainly there are many people for whom the iPhone, in its current form, will not work. But there is not a single, uniform profile for business people, just as there isn't for consumers.
I suspect Apple executives are
highly aware of these different groups, their usage patterns, which features are "must haves", and which features are "nice to have". And they probably have estimates of how many additional iPhones they will sell by adding each new feature, and these probably form the basis of their attack plan for iPhone updates.
The conspiracy theory question is:
Are either Apple or AT&T purposely leaving out certain features to avoid conflict with certain business segments?
For example, AT&T sells the BlackBerry Curve (using the EDGE network, incidently). Maybe they don't want the iPhone to collide with the BB market. Or maybe Apple wants the iPhone to be seen as "hip", so they don't want it to be seen as a business device. As an example in a different business, Toyota fights very hard to promote the idea that the Toyota Prius doesn't need to be plugged in (in fact, it cannot be plugged in), so Toyota has been hesitant to develop and promote a plug-in hybrid.