You're right.
It would be a turned-off for non Sonic fans viewers if it's kinda like Dr. Julien Robotnik and RoboRobotnik V2 thing.
It should be made more simple.
Plus, now that I've seen the film a second time, less rose-tinted glasses for it. I still think the movie is awesome, it's just they retconned some stuff I didn't agree with.
Like making G.U.N. older than Commander Walter stated it was in the previous film. Or Knuckles TV series claiming Agent Stone and the Buyer were once members of G.U.N., with Dr. Robotnik being the leader of G.U.N.
Kinda makes watching the film hit different knowing Dr. Robotnik was leading G.U.N. at the time, but no one told him he had his grandfather in the basement all this time.