Yesn’t
If you go by the meaning of the word, being an visual style, or by the japanese definition, just a short term for animation. Then yes, it is an anime.
If you go by the popular meaning of the word, animation made in Japan. Then no, it isn’t.
It doesn’t really matter, enjoy whatever you like and let others do the same.
I don’t see why not. They were produced by a japanese company (although only partially). But if you don’t want them to be, then they are not. In the end it all comes down to personal preferences, where no one can be wrong.