The point is that people make generalizations that they don't realize based on their personal experience. For example, I can make tons of generalization about how nice India is for tourists as an Indian (I currently live in America but travel back for family and as a tourist occasionally) but someone who's white might not share that same experience because they might be hounded by scammers and people looking to make a quick buck off of an unsuspecting foreigner.

Similarly, cities and people in the midwest might be great if you're straight, white, and "normal" but that might not be true for everyone. Will people be as welcoming if they see you as an outsider? Maybe. I try to keep an open mind but I also can't be 100% sure.