> I cannot think that you have a lot of experience with all social classes if you think this.

Yeah I really can't take this share by OP seriously and can't help but wonder if the post is on some level clickbait. I keep my circle pretty diverse and have had a few jobs where I interact with people outside of my norm... I've met some people that truly lack in areas that are clearly identifiers of "intelligence": critical thinking, problem solving, memory, communication and social skills... Intelligence can be defined as a lot and yet I still have met some people who are clearly an idiot - and I don't really consider myself to be super intelligent either. After getting into the workforce, I would maybe describe myself as above average but that's only because of the people I've met bringing down the average to below my level.