Not sure why it being 2d and needing optimisation or whatever is so hard to believe. Doesn't mean it was running bad, could easily be something unique to pc, like high refresh support that needs fixing. Plenty of games have come out on pc, completely broken for high refresh users. Sonic at 144fps would be a glorious thing. Being SEGA, it wouldn't suprise me if it's just incompetence or an intentional delay, but it's not a huge leap to see that the pc could use a little extra polish for unique issues.