I'm genuinely asking. They must have consulted with lawyers and believe it is legal.
But even if their TOS say they reserve the right to change anyone's plan at any time... that seems like one of those clauses that judges always strike down.
This is just flat-out providing a different service than you contracted for. This is like if I order a $200 SSD from Amazon and instead they ship me a $300 SSD and charge me $300, and there are no returns if I don't cancel the order before it's fulfilled.
I don't understand how this is legal. So I genuinely want to know:
1) Is this actually legal? If so, why haven't laws been passed against this kind of corporate bait-and-switch behavior?
2) Is it illegal but just doesn't get enforced? If so, why not?
3) It is illegal, and there will probably be a class action suit, but T-Mobile has calculated they'll still make more profit including a settlement? In which case, why aren't settlements more punitive?