This request by ATT is a desperate grasp to stay relevant.
ATT has one asset, and that is countless miles of copper strewn about the country. Very old copper. Aging. Decrepit.
Where I live there are a couple ways to get DSL service, but they ALL lease the ATT phone lines. I've had their service from a local telecom, and there were TONS of problems, and all of the problems were with the crap ATT phone lines themselves.
The copper works fine for voice, and will work for data as well, up to what, 20 megabit MAX? Most places can only manage 3 megabit, some 1.5 megabit under ideal conditions, such as no rain or high wind recently.
If the very definition of "Broadband" moves to 10, ATT will no longer be able to call what they sell broadband. This is because the infrastructure that they have milked to death and are likely unable to truly maintain at this point will be unable to provide that service to many places.