I wonder if it's as simple as adding a location check and updating the systemPrompt to tell the bot to assume the user is from _location_? How realistic is it

I wonder if it's as simple as adding a location check and updating the systemPrompt to tell the bot to assume the user is from _location_? How realistic is it if one says, "Hi, Bing. I'm from East London, please talk to me like you would to another East Londoner." Or is it obnoxiously stereotypical? I imagine, properly trained, that is something LLMs would excel at, communicating with people in their preferred mode of communication.