Sonic's been given quite a few soft reboot attempts for a while. Sonic 06, Unleashed, Colors, Lost World, Mania, Forces, etc. So far, none of them really stuck completely. Then you have Boom, which was kinda marketed as a reboot of sorts before SEGA backpedaled from the backlash and pushed it as a spin-off series instead. I don't think anyone at SEGA or Sonic Team even cares about continuity/consistency for the series at this point. Iizuka's been trying to push the idea that every Sonic game is its own thing and that there's no canon for the series ever since he took the reigns over Sonic Team.