The hype surrounding this game always seemed to have a weird faux-hype aura to me, as if it was being projected by people who hadn't touched Ninja Gaiden 3, had little experience with the franchise, and were only interested in the game because it's a Wii U launch title, Nintendo is publishing it, and "Team Ninja is fixing it". Pretty much everybody disappointed with Ninja Gaiden 3 has stated ad nauseum that Ninja Gaiden 3's fundamental problems were not the lack of gore, the absence of variety and levelling systems, ease of play, or anything like that. These were problems, but not the reason Ninja Gaiden 3 was considered a poor game. It's a poor game because the core mechanical design, encounter design, pacing, and game design is just plain shitty. For many people the possibility of a good Ninja Gaiden 3 could only exist if the entire game was remade as something different, because the issues with the vanilla release are that deeply rooted in the design.
Maybe they pulled it off, I don't know and I won't be finding out first hand because I'm not going to risk it, but I'm not in the least bit surprised to hear someone familiar with the franchise finds Razor's Edge to be just as much of a turd as the original NG3.