In which way, though? If you compare Storm with an average human in terms of physical attributes/things she can do then sure but not every mutant is Storm or Jean or Bobby or Mags. It's always funny to me in terms of intelligence the biggest brains in marvel are usually human. Marvel often says if nature is left to run its course mutants will be the dominant species but that's not much different than saying humanity should have died out in its earliest days because they are not as strong/fast/agile/durable as some animals in the wild (I'm not making a comparison between mutants and animals, I'm simply saying that statement doesn't hold much weight in reality). Humanity's defining attribute is how they bend nature for their own gain with science and technology. If mutants are to claim superiority (some do) it should be done through technological advancements, not how powerful some mutants are compared to humans. Now if x-gene made mutants a more intelligent life form on average, I'd agree.