It also lists some "castles" that no longer exist, e.g., Fort Detroit, which was where downtown is and very much not extant (and not to be confused with Fort Wayne to the southwest of downtown, which does exist but isn't on the map). This is just some AI slop wasting our time.
I find the word "castle" can be a little vague, like with Neuschwanstein Castle, which is really more of a palace. I don't think it's worth battling too much about what is or isn't a castle. I don't think you could come up with one set of castles in the world that satisfies everybody.