It is not the entire city, maybe 80% ... there are still some small enclaves that are very nice Canton, Locust Point for example. But you are surrounded by very dodgy areas. the police department is undermanned and overwhelmed, the schools are a disaster, and property taxes are insane. There are two world-class hospitals though, Johns Hopkins and the University of Maryland.
True, but Johns Hopkins hospital is in one of the worst neighborhoods in Baltimore. (And that's saying something)