AZ, there's tons of very nice areas in Mexico that are unaffected by violence, like the touristy resorts Cancun, Playa, Cabo, etc. Mexico City is also a very nice city to visit.. it's often compared to Paris due to the amount of culture and museums.

It'd be like if someone says Italy is a shithole just because there's a few bad areas of Calabria, Napoli, etc.