If you're looking to say humans are categorically different from every other animal -- that is, that we have something
none of them do -- then you're operating with such a level of granularity that it's necessary that you overlook small differentiating factors. The issue is not "why are humans unique, just like every species is unique" but "why are humans unique in a way no other species is?"
And if you take a human and ignore their facility for language, you will essentially have a regular ape. If you take away our capacity for culture and technology, you don't have an animal that rules the world uncontested. Whatever other differences we have are moot in comparison. (Take Stephen Hawking as an example.)