What about BRIC companies?
China in particular is producing a great deal of big-tech software and hardware, and their government is applying explicit and deliberate political manipulation of their technologies. Where does that factor into this kind of debate - how will a bunch of legally restricted baby-bells compete against external government-backed monopolies?
(e.g. the online-store battle between Epic and Steam at present; Epic is 40% owned by Tencent, a Chinese company worth over $500 billion. That's where all the money to buy exclusives to starve out Steam is coming from; what happens if they start to offer social-media features and the Chinese government decides to get involved?)
From my personal perspective, I can see a lot of benefits to breaking up companies and silo'ing their access to personal data. But at the same time, the USA is no longer the only 800lb gorilla in the arena!