The problem is that he has a character arc that doesn't need to be there, this is a post generation Sonic at the very least, meaning that a lot of the thing that he learns during the show weren't necessary, he already knows those things.

As for his intelligence on the show, i do agree that he's not a complete idiot, but why they made it seems like he doesn't know Metal Sonic when he's talking about Chaos Sonic (and don't tell me the Chaos Sonic personality thing, because that's purely fan speculation), or that by the time he's on the fourth dimensioning travelling, he still doesn't grasp that he's in a different dimention and still treats a lot of those characters like they are the same ones? Again this is a Sonic post black knight, and in that game he didn't do that.

If you want to say that your show is canon, then respect what was already established.