I understand the idea, but really its the difference in how he has to defend.
In other teams he has more "defending" but its simpler defending, in a pack with other players.
In ours, while he has to do that rarely, and definitely on corners, the most important defending is 1 on 1 that happens when we inevitably get countered. The counters happen, its not anyones fault, but its the hardest thing to do as a defender, its literally why players like Laporte, Van Dijk are the best defenders in the world. They do all the fancy bits, but can add in with correct decision making in 1 on 1s.
That decision making is either don't be stupid and just foul/kick the ball out (Stones is too timid here), or make a correctly timed tackle (Stones kind of okay here), or jockey them out wide into a difficult position for when our team can come back to defend (Stones doesn't think about this enough).