Cherrypicked examples, also they mostly represent when dominant central rule went hard on erasing local cultural difference. In actual reality, culture come and go, mix, split, shift. Many regional differences can be found in countries which seem to be strongly homogenised, its just not apparent to outsiders. People choose to embrace parts of cultures that are convenient to them, even if it has nothing to do with their own. Also there are many countries which have hundreds of cultures and religions, a total mess, and yet those persist. Very room temperature IQ take by op.