It's even possible to release a good Sonic game nowsdays? I think side-scrolling plataformers, like adventures, turned into a niche game which hardly will appease the younger generations.

I see many of the complains about Sonic on games like Zelda or Metroid, the old fans want the game to still keep them interested but perhaps, they just outgrown the genre. People asking about a dark, mature Link perhaps would be happier playing Darksiders.

I don't think the new Sonic game is perfect though, but I also don't think it's the game for me. I think, however, no matter how the game ended the fans would still not like it.