Your analogy doesn't really exemplify what actually happened. I think this is a better one:
Craig brings a set of high-resolution pictures of a Stradivarius violin to an appraiser. The appraiser(Gavin) goes over them - they all look exactly how a Stradivarius violin would look. However, his colleague(public commentators, in this case) says the only way to really appraise a Strad is to see it in person, and that going through all the trouble of getting high-res pictures when you could just bring it over was pointless. Further, the colleague notes one of the pictures shows a "Made in China" stamp on the Strad, and as such guesses that Craig is trying to con them.
If a "Made in China" stamp in itself made an appraiser instantly discard the violin, then they haven't done their job. Similarly, if Craig had provided a strong crypto proof that he was Satoshi(the physical violin, in this scenario), but people disregarded it just because it's him, then we would match your analogy.
The analogy still doesn't really match reality - the reason why Gavin was convinced is because he used tools that gave him a high confidence that he wasn't being conned. Still, the way Craig decided to demonstrate that he was Satoshi was long-winded and complicated, for no discernible reason.