I'm quite sure the following people (in their prime) would have destroyed any version of Jon Jones in a no-holds-barred street fight:
Haku from WWE (when it was WWF) and WCW (where he was called Meng): He is the most feared man in the history of professional wrestling and was 275 pounds. Yes, I know Professional Wrestling itself is fake but you can go watch YouTube videos about what other pro wrestlers say about Haku.
Alexander Karelin: Greatest Greco Roman Wrestler of all time and was undefeated for a very long time. He was 275 pounds when he was competing and was way stronger than Jon Jones and a way more skilled wrestler as well.
Fedor Emelianenko: Prime Fedor would have made short work of any version of Jon Jones. Prime Fedor was too quick and too powerful for Jones and arguably better skilled as well.
Prime Overeem: He was way bigger and stronger than Jones and used to beat up Jones in sparring sessions.
The Great Gama: He was an incredibly strong Pehlwani Wrestler from India and was never defeated in his entire life and he challenged people from all over the world. His workout routine alone was far beyond anything Jones is capable of. He was much stronger than Jones by a lot and a more skilled wrestler as well.
Hakuho Sho: He was the longest reigning Yokozuna Sumo Wrestler in Japan. He would just be way too big and powerful for Jones. There are no weight limits in real life.
I am a longtime wrestling fan, I know about Haku, but from what I’ve read and watched Haku’s main feature was a pain threshold higher than any known human according to his co-workers, along with strength and crazy NFL-like athleticism throwing that body around like he was Daniel Bryan, but Jon is a professional fighter man. Haku had some tough man competitions I believe, but c’mon now he never even got the title once.
Plus pro-wrestling back in the day was different, you didn’t pay your dues unless you allowed someone to break your own leg. I think Haku may have had some fights in Japan, but he wasn’t so old to the point where he could have fought Don Frye in Pride.
I will give you Fedor, particularly back in the day, definite possibility but I also think Fedor was maybe a bit better than DC athletically and just more well rounded as a fighter. Fedor had absolutely no fear though, and Jon has admitted to being afraid on several occasions.
Alistair? I have read that he made Jon cry with leg kicks, but that’s training and probably kickboxing sparring. Jon takes Alistair out, the chin is too suspect and I actually doubt the functional strength of Overeem, Jon Jones isn’t getting kicked in the face by Travis Browne, Shogun KO’d Alistair as well.
If Overeem had done better against Ngannou I would have taken it more seriously.
Maybe Brock could have done it, perhaps he’s the only one with the strength and speed combo to hold Jon where he wants and beat him down against the cage ala Mir at UFC 100.
Sumo wrestlers dude really? I mean it did work out for Lyoto for a while.
I’ll give you this, Jon had trouble with some light heavyweights he had every physical advantage over, and some guys close to his size nearly drawed or perhaps probably should have got the nod against him but in my opinion Jon has found ways to win even in fights he faced adversity, he has always adjusted,, and never even been seriously rocked in the UFC.
Have we seen anyone land any knees or kicks to the head of Jon Jones ever? Has anyone ever even put him in a sub other than Vitor?
Jon had a creativeness in fighting that he doesn’t utilize as much today, and he is probably starting to slow down due to age but everyone you listed that could possibly beat him hasn’t, doesn’t have a positive record other then Reem, and is either dead or too old.
I do think Werdum could have done it, and I do give Pride Fedor a damn good chance.