We have no idea when we're getting Metroid Prime 4. It might not even be next year. The whole of our info on when we can expect it is a logo stating it's "Now In Development For Nintendo Switch". That's it.
No major title is ever going to be released between Christmas and New Years though. Those are just placeholder dates.
Yeah - those are definitely not coming out during those dates. But, those are the dates Amazon currently lists them as, so that's what I've used for now. Once they change, I'll update the OP...