Joyce is on another planet to what Carnera was, no way could Carnera get an olympic silver medal, he wouldn`t have even got into an olympic team, Joyce is far better in every department and Parker would have destroyed Carnera, Dubois would have to.
I will start by saying that Joyce is still a bit of an unknown quantity, while Carnera is if a divisive quantity, then one as known as he is ever likely to be. As for his future in the division, I would say that his ability is no his side, but time is not. Carnera should probably still be the favorite on paper, but it has also reached the point where it might be reasonable to pick Joyce on styles.
Saint Primo strings together a twelve punch combo that can't be caught on film and vaporizes Joyce's face down to the bone. This content is protected
Joyce is far better in every department except maybe hand speed. I can't think of a single boxer with slower hands than Joyce. Not a bad fighter overall, but he moves like a sloth. Joyce would win the fight, but I believe it would go a few rounds. This would be painful to watch. Probably the slowest moving boxing match of all time. I see Joyce slowly bludgeoning Carnera and stopping him in the 5th or 6th, winning every round along the way.
On no planet would Carnera be favorite to beat any modern fighter. Joy Joyce is slow and unskilled but Carnera is so slow he makes Joyce look like Roy Jones Jr in speed. Joyce would starch Primo in 1 round.