I don't see a lot of reviews for this yet and I was shocked to see it's already been released. So is this one of those situations where the publisher did not provide review copies? That's usually not a good sign, typically in anticipation of poor word of mouth.
I think there are probably two approaches to reviewing this and they both have an audience:
1. How good is game on its own merits without the context of it's IP?
2. How good of a METROID game is this?
For me number 2 is what matters. I'm not interested in Metroid games that don't play like Metroid games. I never bought Hunters for that same reason and I'm also really not that interested in a multiplayer shooter on a handheld either for that matter. This is probably not a poorly made game so 9 review is completely fair if the reviewer had a great time with it. But I can also tell from the review that I wouldn't be interested in this game.