I've lived in a big city for years now. Never seen anybody get mugged, or shot, or carjacked, despite doing activist work that often has me visiting poor minority neighborhoods.
The only time I ever really felt uneasy was when I had to walk alone at night through a neighborhood where all the businesses had bars on the windows. Worst thing that happened was a couple of people asking me for money, and they didn't give me any shit when I said I didn't carry cash.
But any time I visit the small town where I grew up there's always someone or another acting like I came back from a fucking warzone lmao
It's more than just not knowing - a lot of popular media feeds the idea that cities are all warzones directly in to their heads, making up whatever details are needed to keep up the narrative. The average chud lives in a comprehensive media bubble telling them that everything is NYC 1970s bad but worse, all the time, when the exact opposite is true - Cities are safer than they've ever been in the US, overall violent crime rates continue to fall, Cities are generally not the most violent places in America by a good margin.