I'm a bit sceptical too ... but if this happens to be true... someone will have to rewrite history...
I'm not sure where that person got their information, but I think we all know Sonic was in fact based off of Chef Sonny Porcupine back in the '80s, who was a mascot for Orange Quasi, a long forgotten Swedish company that tried making food fun with a mascot before characters like Trix the Rabbit made him look inferior and they retired the character shortly before bankruptcy.
Higher quality here: https://pm1.narvii.com/6787/c036d21c410ce266337c4621cff521d8c04b2b54v2_00.jpg I say it's fake
I'm finding all sorts of useless bits of information just by making comparison pages on the wiki. Like: the "connector" tiles when the blue tubes insersect each other in Chemical Plant Zone is slightly too high in the Nick Arcade prototype! Two player mode uses the single player spawn points for Tails. Which means player 2 always starts with a disadvantage! The light-up trees are smaller in the final game! Red pixels in Genocide City Zone! What a world we live in.
Have another one: Between the Nick Arcade (left) and Simon Wai (right) prototypes, Sonic's underwater palette for Hidden Palace Zone changed slightly. Nick Arcade's is the palette Sonic uses for Labyrinth Zone in Sonic 1. I think this might be the most significant change between the two versions of HPZ. Aside from the debug mode options and the music.
TCRF I knew they mentioned it before, but this is still neat. The Nick Arcade palette looks worse on Tails, and the Simon Wai palette is in the Nick Arcade ROM but not yet properly implemented. Also note how this also means the teetering animation in the Simon Wai palette replaces a shade of dark red used for the lower pixel of Sonic's mouth with one of Tails's oranges.
May as well post this here. There exists uncompiled data in the Sonic 2 Simon Wai prototype. All it is really is a bunch of DC.B's for Aquatic Ruin's/Neo Green Hill's chunk data. It included a comment in Shift-JIS describing its compression. https://tcrf.net/Proto:Sonic_the_Hedgehog_2_(Genesis)/Simon_Wai_Prototype#Uncompiled_Data
That is the more disturbing alternative to blue arms yes. It's like they got everyone else right, howd they fuck up the most established character of all of them. Also how does tails fit in that plane?
Amazingly, they remembered the Tornado's booster, which is more than can be said for the Sonic 2 ending.