I missed seeing that Medium article. Like IQ, smart is a bit too broad a concept. In some domains I am rightfully considered "smart" but I've been known to have done things that were arguably stupid. Smart about what?

The same goes for broad monolithic ideas about groups, be it physical features associated with racial groups, political tribes, wealth, etc. They are not all the same, though there will probably be some degree of tribal influence or conformity. How much? Assumptions can rise to the level of stupidity at times.