Earlier quoted context omitted.
The regulators could have forced the big four carriers (now three) into a common carrier model. In that setup, all cell providers would effectively be an MVNO, and the three (then, four) physical networks would be operated at arms length from the consumer facing side. Also, the four networks could be structured so that their financial incentives were to improve cell coverage and bandwidth instead of undermining each…
I mean Sprint was strictly CDMA, so that would be an issue on it's own.
How so? Sprint operated 4G LTE, which is a GSM technology (or alternatively, unified the two, depending on how you look at it).