Actually, there was a much more positive review posted a few days earlier on Reddit as well here: https://www.reddit.com/r/fireemblem/comments/63vq9a/my_thoughts_on_shadows_of_valentia_spoiler_free/
Different people will have differing tastes in games, and honestly, it's probably a kneejerk reaction. I'd rather wait and form my own opinion on the game than take someone else's (possibly biased) review of the game too seriously.
Unfortunately, Reddit seems to be circlejerking again (worse than Revelation, really?), but that's just typical /r/fireemblem