Oooh, 9% of crosses. Imagine all the trophies we'll win.
I'm sure Dave would happily swap his trophy cabinet over the past 5 years with Ederson tbf.
A ball playing goalkeeper (that some people believe is very important) ... how many additional goals would create per year?
I may be wrong, but I don't think that any goalkeeper in the PL creates that many goals that really makes a difference. Especially compared to the contribution of a world class striker. For example, I don't think that Haaland or Kane are going to score less if they don't have a ball playing goalkeeper behind them.
Then perhaps people believe that a ball playing goal keeper will save more goals? Perhaps because he is more "press resistant"? But then again this depends much more on the outfield players, not on the goalkeeper. No matter how "press resistant" the goalkeeper is, I don't think he will save us many goals because of his exquisite passes.
So, in my opinion, for a goalkeeper, it is nice to have this "ball playing" ability, but it is not very important at all.
Am I wrong?
Yes I think you are because you're looking at it the wrong way. Nobodies looking at a ball playing goalkeeper as a creator of goals. Sure it happens now and again from the likes of Ederson (who in fairness is distribution above all else as a goalkeeper and not the way to go IMO) and Alisson when they hit longer balls forward; but that isn't what they are there to do. The purpose of a ball playing goalkeeper is to allow your defence to play higher up the pitch because you know the goalkeeper will sit in the space in behind the defenders and sweep balls over the top; this works three fold, a) when you're in possession offensively the defenders can play higher and compress the play with more players in a smaller space which benefits the clubs trained to play close compact football like City & Liverpool over the last few years, b) in transition where teams win the ball back and realise the higher line team are pressed high their only option is to hit a long ball in behind, goalkeeper picks up possession and team are back on the attack, c) when team are playing high and are being pressed by the opposing attackers, the goalkeeper becomes an option to pass to to relieve pressure and build again.
I think what you're getting at with the goals creation specifically is the quick distribution rather than ball playing, as it relates to quick throws or long kicks, which directly result in goals. De Gea's distribution has never been quick regardless of which coach he's worked under; whereas Schmeichel and Van der Sar for example were great proponents of moving the ball quickly when the opportunity presented itself and it made a different to our overall play but I wouldn't put that down to either of them being "ball playing goalkeepers" it was them reading the picture in front of them quickly. Some goalkeepers do and some don't, and it's very difficult to coach so not something I've ever held against De Gea.
For me having a progressive on ball goalkeeper is less important than most; my view tends to be as long as you're at a reasonable level with the ball at your feet you'll be good enough in most teams; see Courtois & Donnarumma for example (the issue with De Gea is that he's a level below them as well which becomes problematic). My gripes with De Gea are much more related to areas of goalkeeping that have been part of the game for 30 years or more at this point. You expect your goalkeeper to relieve pressure on the defenders, be that by catching crosses, sweeping behind the defenders so they don't have to run backwards into space unnecessarily thus turning their backs on the attackers, being an option for the backpass (heck the backpass rule was brought in because goalkeepers were making themselves an option to pass to to relieve pressure far too often!). We've never really had that with De Gea, he doesn't generally take the sting out of games as he doesn't deal with crosses and pushes balls out and allows sequences to play out that if he was more proactive he could easily have dealt with. Preventing opportunties which you refer to is far more down to a goalkeeper being proactive than their "ball playing" ability.
For Ten Hag it is clear playing from the back is very important to him, so it's pretty clear that while a top "ball playing" goalkeeper might not be a priority for you I'd be very surprised if it isn't for him.