People change. Different environments while growing up lead to a person getting a different character. We are shaped by out environment and by the relationships we have with the people around us. Experiencing different things will lead to a different result.

As long as Naruto is still the son of Minato and Kushina and as long as it is explained how/why Naruto has become different from the canon, I don't mind.

I look at myself. I grew up in a ghetto-like environment up until I was 14. I used to be as ratchet as they come. Loud, getting into fights on a weekly basis, racist, with no respect for old people or other people's religion etc.

But, at the start of high school, I moved to a different neighborhood. Surrounded by civilized and educated people and attending a good high school had slowly changed me. It had not happened overnight, it had been more of a gradual process.

However, now, 13 years later, I am a completely different person than how I used to be. Completely different. And that is simply because of the change in the environment I grew up in.