Problem is, the two companies merging wouldn't have created any more capacity at all, since TMobile's spectrum is already saturated, same as AT&T's. AT&T owns plenty of unused spectrum, but so far have failed to build new towers to take advantage of it. In the proposal, AT&T listed a laundry list of how the merger would provide manna from Heaven for all mankind, but the details showed they were full of crap. For example, AT&T said the merger would create 25,000 jobs. Several pages later they showed where several facilities would necessarily be closed and duplicated jobs would be eliminated. When the numbers from facilities and lost jobs were crunched, it wasn't a total of 25,000 additional jobs gained, but more than 20,000 jobs lost. AT&T also said the merger would immediately solve the bandwidth problem, but again, many pages later when they show available and used capacity for both companies, that wasn't possible.
There were about 20 items that AT&T tried a little too hard to fudge in their favor, but in the end the FCC wasn't buying it, especially since the two carriers with the highest percentage of customer complains are AT&T and TMobile, and AT&T didn't present anything in the way of any fundamental changes to address it. If the merger had gone through, we'd be left with AT&T and Verizon, with a scattered few inconsequential carriers who could have no effect on competition or innovation. There would be in effect a massive duopoly.
