I'll be honest, you sound like someone's grandma who calls every game console a "Nintendo" and every game character "Mario". So what if the general public can't tell the difference between Samus and Mario? That doesn't mean we ban Metroid.

They're the same genre, but obviously not the same game. Is only one voxel sandbox game allowed to exist in the world? What's next, only one platformer can exist? Only one action movie is allowed to exist? Only one power metal band in the world?

Again, aesthetic is not copyrightable.