As a Quebecois, I like that Canadians like poutine. I don’t like that they pretend they have invented it. I also like that they like maple syrup and the traditions surrounding it (cabane à sucre). I don’t like that they appropriate it as a thing of their own (we produce 90% of global maple syrup).
So it’s fine for a culture to pretend to have invented something or take something as their own as long as that something is from a culture that happens to be in the same country?
To me, that’s cultural appropriation, no matter whether it happens within the same country or not.