I wonder if they might also be getting a biased view of various cities because of the profile of their customers. Maybe their customers tend toward affluence or to living or working in certain parts of towns, which would give a slanted view of the traffic in those towns.
The only reason I hated SA traffic was it's like everybody's cars were speed limited to 55 mph whether it was rush hour or not. Or maybe I've been there on "slow day"?
Yeah, Austin's freeways were designed by a retart and the traffic sucks, but it is not even close to the nightmare of Houston's rush hour. And yes there are some unreal shortcuts to get around Austin's traffic including the Great Northeast Passage that cuts 45 minutes off a drive from far south to far north ATX on I 35 at rush hour (no it's not a toll road).
Houston traffic aint that bad. Ya'll got enormous 10-lane freeways and many feeder roads to take instead. I would say NJ/NYC is the worst because in many cases, there is no alternative to the freeways/highways and there are certainly fewer lanes.