Yes? Imagine millions of devices spamming your radio and core network to death?
>because the carriers were worried about their networks crumbling.
? The performance just want not there until 4G LTE came around. You could only push 2G and 3G so much. 2G was built for voice, data was bolt-on. Just physics. If you have another brilliant idea on how to solve that please comment.
When the iPhone originally launched on 2G, it offered access to the "full web" via Safari, bypassing the carrier's proxies. Many carriers setup dedicated GPRS APNs specifically for the iPhone, which (with the exception of Blackberry), was somewhat unprecedented. The iPhone did place massive strain on networks as a consequence.
Then you had companies like Blackberry, who invested significant R&D in minimising radio traffic to play nicely with carriers - and the value of that R&D evaporated because Apple changed the rules.
Carriers were terrified of the iPhone, because it represented a fundamental shift in the dynamic. I was working for a carrier outside the US when the iPhone 3G launched. It was the first model to be available in my country, and carriers were not convinced they would even make it available. The carrier I was working for only made the decision to move forwards in supporting it four weeks before the launch date. Even with 3G (UTMS) being widely available at the time, it still proved problematic.