Wasn't that before they bought out Sprint, though?

Newsflash: T-Mobile is a big provider. They took some standard European practices, also technology, and then pretended to be a small scrappy startup in the US until they had enough of a customer base to return to their usual monopolistic ways.

The only thing that keeps them half-way in check over here is forced unbundling: If you have network infrastructure you need to let other providers use it, at regulated prices. Which is really necessary as they inherited every single landline in the country from the old state monopoly.

Be glad that the postal service got broken up into telecoms, postal/parcel and banking before getting privatised if it hadn't it would be an absolute scourge on the world. Imagine them cross-financing such market takeovers with the additional resources from the largest logistics company in the world (DHL). Banking sector is less impressive right now Deutsche Bank doesn't know what to do with it. I have no idea why they even bother, they don't care about end-consumer banking there's no money in that.