Personally, I find Squawka's stats to be even shittier than most, especially their "attacking score", "defending score" and "total score", which seem to be total shite they pulled from a dead bum's bum. But I did notice the same thing about Jones a while ago, all the stat sites rates him highly -- Whoscored has had him as United's best rated player all season. Without having a go a Jones, I think it just goes to show how dubious these stats can be, perhaps for defenders especially. I think in Jones' case, he has particularly good numbers because he fucks up a lot but usually recovers from it -- so he gets good numbers for putting in the tackles and the clearances, where a better player just sees off the trouble before it gets to that point.
But it's still undeniable that he does do a lot of things very well and is still a young player. Ultimately it might be that he has great instincts but not a great head for the game.