That ending doesn't seem very controversial or groundbreaking, or that people will talk about it for more than a few months other than 'best/worst cv endings' in the classic threads subforum.
The game itself doesn't seem like the worst thing (considering that this series boasts such AAA titles like curse of darkness, Judgment, Legends, and Haunted Castle), or even all that bad. But it's not the super duper quality action title or whatever that they kept boasting it would be. It seems like this generation's Lament of Innocence, which had similar hype as the ultimate 3D Castlevania but it was only good and nothing more.