There are some subtle, but important differences here.
- You can buy the phone outright and pay a monthly bill for the service only. This wasn't possible before. You can also buy that phone from someone other than the service provider, making it cheaper.
- The contracts are structured in such a way that they guarantee that you spend at least $450 every two years on a cell phone. Since the service charge now scales to the price of the phone, it is possible to save money by getting a cheaper device.
- Should you decide to keep your phone past the two years, your monthly rate drops, whereas with a contract the rate doesn't change.
- Should you decide to leave T-Mobile, you're liable only for the unpaid cost of the phone, not an arbitrarily-determined ETF.
While it might be fair to argue that all T-Mobile did was introduce transparency, that feature alone is enough to alter the way you approach your service, and provide you with several avenues for savings that weren't there before.