"Good customer support" is a matter of perspective. As customers, we prefer highly qualified responders who understand and solve our problems. Most businesses prefer to pay as little as possible to people who are just good enough to keep you from canceling your service.
At the scale of AT&T's business, if they can keep you just this side of canceling, they will consider their customer support "good."
At the scale of AT&T's business, if they can keep you just this side of canceling, they will consider their customer support "good."