To me the only stat that matters to forwards is goals. You have never seen me quote this success rate, xA, xG, nonsense to rate and justify my like for a forward. Rarely ever.
And lol Salah. Here we go:
https://www.youtube.com/watch?v=iZ68OskGqow
Link me to Dembele scoring a goal with this level of control and composure on the ball. Just because Salah doesn't spend every waking moment of the match sprinting and crossing attempting to beat his man doesn't mean he's the inferior dribbler.
Here's another one:
https://www.youtube.com/watch?v=CWmZm-EIAsg
Another one:
https://www.youtube.com/watch?v=ecs6BHg9Kag
This is quality your "expected dribbles, progressive carries, successful dribbles rate, dribbles per game" aren't capturing. This is quality that Salah produces on a regular basis. You can probably get 10 instances of him producing this sort of quality within a season, with 4 or so of those instances leading to goals. There are about 10 goals of this type that Salah has scored since his arrival in 2017/2018.
There's not one instance of Dembele ever dribbling at this level of quality and control in his entire tenure at Barcelona, Dortmund, or Rennes. Spinning and feinting past 3 players whilst the ball is glued to your feet without ANY need for pace whatsoever. This is a goal that all great dribblers can do. Neymar does this, Messi did it, Ribery did it, and so on.
Dembele has never and will never be able to do it. Because what he does is not "true dribbling", it's just using his pace to outrun his marker. Technique at an elite level is something he doesn't have.
Dembele may have an instance of exhibiting close control with the ball once every 40 matches or so, but he will never have the composure and awareness to GUIDE the ball into perceived "closed areas" of space to open them and turn those areas into lethal areas of space. Dribbling is not just about technique and pace, but also about spatial awareness and composure. It's what allows Ribery, Salah, Messi, and....Vinicius Jr to score goals like these. The lack of it is what keeps Dembele spraying crosses from the corner flag. This is what your stats aren't capturing. They only reward volume and attempts, not quality.
Excel spreadsheets with your successful dribbling rates and dribbles per game will call Dembele the superior dribbler. People who watch the actual games will say otherwise.
And on top of it all, Salah adds goals to it like a true forward should. The only stat that should matter.