I am not sure you are interpreting the map correctly. The red-brown tones are less-dreary, while bright red is more-dreary. L.A. is squarely in the less-dreary area. See also the numerical rankings.
Actually, this sounds like a great use for an LLM or even boring old machine classification. I am sure Prague and Beautiful are commonly found a few tokens apart in a training set of say, TripAdvisor forums. While "LA"/"Los Angeles" and "ugly" are likely to be similarly co-located.
Just the other day I saw tourists trudging around on Hollywood Boulevard, which is a major shithole. I thought that I can't believe these people aren't deeply disappointed but afraid to admit it.
Your point stands though. L.A. is one fugly city.