I do believe it is about network congestion, at least partially. If they did not throttle or charge extra, way more people would use their phone with heavy usage and WHAM, the network is overloaded.
Charging extra/throttling, etc becomes supply and demand.
Nope. Had an AT&T rep basically say the same thing to me (that it's NOT about "congestion" it's about easing people OFF the "unlimited" plans).
People tend to overestimate the way LTE bandwith is affected. It's NOT the same as 3G (which handles way more congestion because of voice calls... by the way).
Take Verizon as an example. Somehow, magically, even though they have unthrottled unlimited LTE plans, they don't suffer any outages or slowdowns. Amazing!
Or even AT&T. They STILL have unlimited unthrottled iPad plans, and they don't "bog down" the network...
Look, it's a great "talking point" for AT&T to try and fool people into thinking it would hurt their service, but the reality is, voice over LTE is going to create FAR more "congestion" than allowing the few thousand "unlimited" iPhone users unthrottled access, but are they worried about quality of service??? Of course not. Why? Because their infrastructure can handle 20X the load it currently has. That was a major REASON to upgrade to LTE (the major bandwidth advantage over 3G).
AT&T will SELL you as much data as you want if you are on a tiered plan. If you want to use 50GB a month, they will NEVER question you, or tell you that you are abusing their network.
It's only when you aren't paying them for it that it becomes a concern.
It's a scam. It wouldn't slow down anything. Not even if every unlimited iPhone user used their phones non-stop (provided it was all on LTE of course).
Throttle my 3G. Leave LTE alone.
It'll never happen, but don't buy into the BS machine of AT&T PR. They have PLENTY of bandwidth.