Personally I think IQ and practical intelligence differs for a person. I have know many IQ smart people that can solve complex problems but fail to solve or foresee everyday basic problems
Intelligence isn't one dimensional, but the parameters do tend to have a correlation on average. Higher IQ usually means higher other forms of intelligence -- on average. That being said, the caveat "on average" must always be added. On average, on average, on average. Same goes with anything about average tendencies of different genders. On average, on average, on average, averages across large groups do not map to…
But this is biology after all. Most likely, plain improvements with zero downsides, very narrow improvements at the expense of something else, and improvements at the expense of life expectancy, are all possible mutations.