You've got to remember that "at&t" (the current one) is not AT&T, the remains of The Bell System resulting from the 1983 divestiture.
SBC, which started out as a Regional Bell Operating Company named "Southwestern Bell", bought the old AT&T at firesale prices back in 2005 and assumed its corporate livery.
SBC and Southwestern Bell before it, never made a secret of thinking that the 1983 Bell System breakup was a mistake, and has spent the last 28 years trying to put the Bell System monopoly back into place.
SBC, which started out as a Regional Bell Operating Company named "Southwestern Bell", bought the old AT&T at firesale prices back in 2005 and assumed its corporate livery.
SBC and Southwestern Bell before it, never made a secret of thinking that the 1983 Bell System breakup was a mistake, and has spent the last 28 years trying to put the Bell System monopoly back into place.
So, yes, AT&T is a monopoly in the making.