We are not talking about the old AT&T. We are talking down to pre-iPhone AT&T, which at that time was known as Cingular not before that.
They were the biggest wireless (bigger than Verizon Wireless) BEFORE the iPhone was ever announced. Reason for this fact mentioning is that Verizon schills like to scream on how good Verizon is and how their network is perfect and everyone wants on it; well not so much since Verizon had to buy their rank as #1 with subscribers rather than earn them as AT&T has. AT&T, rather cingular EARNED all 70 Million of those subscribers, so some thing tells me they are doing something right.
That's the main point here... but you missed it by a loooong shot.