Such assessment is a good proxy for a certain kind of intelligence only, because intelligence itself exists on a fairly wide spectrum, it is not a binary trait.
'proper' Engineering (MECH/AERO/CIVIL/EEE) is full of memes about this mindset.
CS is just as bad.
Most decent engineers loose this mindset after freshman year but many go on to see them selves as the MVP department of whatever business.
In some ways I think Startup culture fights against this because it's really obvious at small team scale how different skill sets are needed.
Sales is an outlier because compensation for the best can be really good. So, it's got a large group of very talented people and many far less so.
A normal consumer with a normal job is only really going to encounter the lower end of the field.