The thing is, the American market started calling him Robotnik, but the sad thing is as far as canon goes, he's always been Doctor Eggman. This is the unfortunately true fact that a lot of current-form defenders will dredge up to no end. In their mind, Eggman has finally adopted a universal design and personality that stays the same across the comics, games and localizations.
Where this hurts is where the Eggman defenders refuse to consider that Miyazaki and company more or less butchered a good chunk of their audience's childhood memories. Canon is one thing, suddenly twisting it out of shape because someone at Sega of Japan went "You know what? This shit's over! Screw the old fans, screw the Archie Comics and Fleetway readers! Everyone on the Eggman train, fuck that stupid fat American design!" is another.
I understand and accept that, but it feels like Sega didn't realize that Sonic, as a brand, has become bigger than their core team's designs. I don't understand how the two versions of the same antagonist couldn't coexist, and I don't understand why Sega isn't willing to crib from the comics' one or two good ideas. This whole transmedia thing could be a great opportunity for mutual growth, but all I'm seeing is Sega occasionally dropping a line at Archie and going "Oh, hey. We're launching a new Sonic title in a couple months, you mind producing mini-comics where Sonic drives go-karts or surfs or turns into a werewolf for us?"
That's disappointing, honestly.