Mexico City is a crazy place. A place with many problems. Of course, it´s megalopolis and one of the largest and most populous cities in the world. But it is also a wonderful and magic place with a unique energy. The place full of really nice people, gorgeous architecture, majestic history and exquisite cuisine.
Do not pay attention to the sensationalist medias. Enjoy this place as The Gran Tenochtitlan deserves :).
More about Historic center of Mexico City: https://en.wikipedia.org/wiki/Historic_center_of_Mexico_City
More about Mexico-city: https://en.wikipedia.org/wiki/Mexico_City