I like your point- he slammed the shit out of Barnett and he floored Bigfoot- knocked him silly and shut him out as bad as Cain did if not worse.
The thing is with Barnett and Cain, I feel Cormier had an elite skillset that cancelled out their best skills (Barnett and Bigfoots top games). They couldn't employ what they do most effectively because Cormier is too good in that facet. His superior boxing combined with that skill made it a bad night for both Barnett and Bigfoot.
But with Jones, his standup is almost as effective as his wrestling/top game so if Cormier robs hm of his ability to use takedowns because of his wrestling prowess, he still finds himself in a problematic fight with a guy who is a very tricky, sneaky striker- being able to attack from distance as well as to stifle and strike in close quarters like he did against Glover.
I see that as the difference. Against heavyweights like Roy, Mir, Barnett, and Bigfoot (all large and very solid fighters overall) Cormier had the wrestling advantage AND the striking advantage. Against Jones, he may have the wrestling edge but I think he will find Jones' striking and reach very difficult.
Plus Jones is not the type of dude to get wrestled down and broken down with GNP. He was taken down once in the UFC as far as I could count and when Gus did take him down, it was for about two seconds.