I agree, there will always be differences in intellectual capacity. It's not a problem as people are needed of every capacity for every type of job to do the work. There's nothing wrong with someone being of low IQ and taking a job they're capable of fully grasping. Often, I find that people in positions that suit them often do better at those jobs than people ill suited to their position.

For me it's really not about how smart you are or what you're intellectually capable of, it's about how well you do at the job you have. Knowing the nuances of that position and how to handle situations in the context of the job, which makes you a valuable member of society.

It is shameful that people of low IQ are used as an offending stereotype for society as a whole. Low IQ doesn't mean anything in the grand scheme of things; especially when taken in context with someone's utility to society. Some of the most important and helpful people are those with limited intellectual capacity, or holding jobs well suited to people with limited IQ. As an extreme example, say someone who is low IQ works on a farm growing food. That farmer does a good job because they're all suited to the kind of work they do. This allows more intellectually capable people pursue advancements that can benefit everyone including the farmer. Whether designing vehicles or electronics/computers, or even keeping complex systems running... Everyone is important. People of all IQs and walks of life and everything.

I would argue that people of low IQ are the bedrock of modern society. The people who handle the day to day service needs of the general population. They provide, and maintain the framework in which we all live. Without them, or someone to do those jobs, I believe that society would collapse.

Of course, I continue to believe that everyone of all walks of life should continue to make efforts to improve upon themselves; gain more knowledge and "move up in the world" as they are capable... But no matter what, we still need people who will grow, cook and serve food. We still need people to stock shelves and drive trucks. We still need people to do so much of the work that makes our lives possible at all. Not everyone can be an Einstein. While the notable inventors and thinkers get their names in history books, that progress is built on the backs of hundreds or thousands of "menial labor" workers that helped get us to the point where people of high IQ can spend their lives working on these problems and finding solutions the rest of us couldn't possibly have thought of.

We're all a part of the society in which we live, if we're doing our best to contribute to that society and provide meaningful progress to future generations, then everyone is important. Not just those with fame and notoriety in the history books.