Keeping up to 4 laying hens responsibly in a decent-sized urban back yard is actually quite rewarding, and requires little work (average 5-10 minutes per day for up to 4 eggs per day). If you treat them like a factory then yes, you will get "vile creatures". Input=output. Chickens kept in poor living conditions can be expected to behave like prisoners.
I am not aware of any large cities with ordinances that allow for roosters, but even so they are a hell of a lot quieter than the dogs and ambulances and drunk people that you deal with in the city.
As to the smell: as long as you provide clean bedding materials, move their coop at least twice a year and compost the waste it should not be an issue. And you'll end up with ample quantities of the best fertilizer out there for your garden.
All this depends on having a patch of land to work, which the system in the article is a clever alternative to if you have a desire to be connected to your protein source.