He’s playing Davis Cup this week, no ?
It seems odd to talk about a 20 year old at a crossroads but I agree with you guys that what Holger does now can impact whether he can jump up to the “greatness” level. As El Dude pointed out in other threads, the window of opportunity statistically speaking to quantum leap up occurs in nearly all cases between 19 & 22 years of age. "He's only 20", yes, but there are things that can be established in the next 12-18 months going forward as to where he will settle.
Again, we are spoiled by Alcaraz, but there are signs with Rune, Holger has a positive head2 head with top ten players, and he has wins against the top 3: Djokovic, Alcaraz & Medvedev, (contrast with 22 year old Sinner who plays well versus Alcaraz but otherwise is 0-11 versus Djokovic, Medvedev and Rune himself). Best results at Slams this year was one 4th round and 2 QTRS back to back. He's at 20 currently ranked. #4 so the big question is will he go upward from here or will he regress.
The back injury is worrisome, but this late fall HC season will be telling; if he's physically recovered and if the coaching situation impacted him headwise with Patrick and Lars butting egos earlier this year. Glad he's got that settled for now, but no doubt the big expectations are squarely on his shoulders. I do think he's incredibly talented but can he balance the physical, emotional and mental to be a great champion is the burning question. The tournament grind can get to even the most gifted players.