I believe he was referring to your spelling of "Kuurahk" with two u's.
An urge to have adventure and go exploring, these are usually traits of boys. Note that I say usually. Can there be females with those traits? Yes. Are there a majority of females with those traits? No.
As for the topic at hand, I think I get the issue. if you change the gender of a character, you have two options: you can change the personality to match the new gender, at which point you just have a new character. Or you can leave the personality the same, at which point the gender change was pointless and only served the idea of "gender equality" while not actually doing anything for it.
Now, personally, I don't care. But I know why people do. You want to make a female Toa of Air, fine. But it won't be Lewa. You want to make Lewa female without changing any other aspects? Go ahead. But then it is just a pointless change.
One last issue I have with something you said:
This is not a good reason to change a character. You can tell a new story with the same characters; sequels do it all the time. You could have the exact same Toa Mata as before, in a different situation, and you have a different story.