They can do whatever they want. The old unlimited plan was never intended for individuals using streaming services which is why they got rid of it. They can put anything in the contract, thus allowing new features to not be available on grandfathered plans.
People need to shut the hAll UP and get over it already. If your not happy SWITCH PLANS or providers.
People with opinions like this really concern me.
I don't know if it was necessarily "individuals using streaming services" that prompted AT&T to discontinue offering the unlimited plan. It was more likely the incentive to sell data in blocks to prevent satiation and retain the ability to charge more per month and/or modify existing data rates as they see fit. We've seen this with phone minutes, texting allotments, and most recently with data allotments. It's not like this has come out of no-where, AT&T is quite predictable.
What really makes me sad is whenever I hear the argument "don't like it? leave!" as if it is supposed to solve problems. Capitulating to laws and new policies never leads to change. It leads to inevitable further restrictions. Yet, individuals like the OP that speak out against such restrictions are given labels such as "crybabies" and "whiners." Le sigh.
What we have here is a powerful company (AT&T) creating absurd artificial restrictions in how paying customers consume data in an effort to strong-arm them into making cellular plan choices. The closest analogy I can think of is the following:
You have two supermarket customers that want to purchase a cheesecake. One customer (A) has a loyalty card membership, the other (B) does not. The supermarket no longer wishes to offer benefits to the loyalty card member. Customer B purchases the cheesecake and leaves the store. Customer A purchases the cheesecake, but the store tells them that they have to consume the entire cheesecake before they leave the store. There is no reason the cheesecake can't be eaten outside the store. The market offered both cheesecakes for sale and willingly sold them. However, they make necessary restrictions in how a product can be used.
AT&T is doing much the same thing in dictating how we can use data that WE pay for. I would even buy into the argument that allowing all customers to use facetime over 3G would "congest" the network if AT&T ceased selling new data contracts to new customers. After all, if their network was in that much jeopardy, they wouldn't have any available bandwidth to give to even more people, right? Oh, wait...
