The way things look around here

I asked the cabdriver on the way from the airport what was Mexico City's biggest problem, and he said it was traffic. But from the vantage point of the pretty neighborhood where I'm staying, La Colonia Condesa, congestion doesn't seem to be a problem at all. All I've noticed is the old-timer on his knifesharpening bike, and the whistle he blows that sounds like a loon, the faded altar to Mary at the gas station and another at the cross of a busy intersection, and the young workers eating tacos at sidewalk cafes.