Since you provided no citations yours is just an opinion at best. I'll throw mine in. You are wrong, IQ is about context. The more context you have about a subject the smarter you will seem. Your IQ will increase proportionally with the number of subjects you acquire context in. It is better if the subjects are diverse. Also, the more context you have the faster your processing speed will seem to get (In reality it stays constant, your neurons will only fire so fast)

Sure, raw learning ability, or memorization speed which is what you are talking about, matters. But as long as you don't have a learning disability it pales in comparison to context. And we all have pretty much the same learning ability. Also, those people that are really smart have put in thousands of hours to acquire lots of context. The genius who can absorb new material by reading any subject in a single pass is a myth.