A few years ago, I was in a group of people who went from Jacksonville, FL, to Wallace, NC, to help clean up after Hurricane Florence. When people asked where we were from, we said, "Jacksonville," to which they would say something like, "Oh, I go to church in Jacksonville." We were from the twelfth-largest city in America (population: 949,611), but we had traveled over 400 miles, and were now close enough to Jacksonville, NC (population: 72,723), that to the locals "Jacksonville" meant the smaller city that was only 40 miles away. Similar things happen with other identically-named places: in 2013 these students went to the wrong Fayetteville, and of course who could forget brake-parts scion Tommy Callahan mistaking the Columbus in Georgia for the one in Ohio?
I'm working on an idea of pairing places with the same name and developing an equation that would predict the places where the word means something different to the listeners. I figure it needs to include the population of the place (so the larger city like Las Vegas, NV, will be recognized more widely than the smaller city like Las Vegas, NM) and distance from the listener (someone down the road from Jacksonville, NC, assumes the nearby one, not the larger one). I think it will also need to be based on metro area population, not city population. Some "major" cities in the US are now quite small (Pittsburgh, PA, is now the 68th-largest city in the US, smaller than Aurora, CO). When I get this fleshed out, I'll share some maps showing what I find.
One thing I don't yet know how to account for is cultural weight. For instance, almost everywhere in the US if you said, "My cousin lives in Hollywood," your listener would assume the neighborhood of Los Angeles (population: 146,514), not the city in Florida (population: 152,511). I'll try to figure something out.