It's part of a coach's job and the captain too, as leaders, to be motivators. It's a completely independent trait from being tactically shrewd, but it's nonetheless very important when you have a coach who can motivate his players. It's all psychology, but I haven't seen a psychologist on the sidelines motivate the players. But hey, I'm all for creative solutions! Hummels tried to motivate his teammates for some time, but I think at some point he gave up, especially when Reus came. He probably was like: "It's your job now, I'm done." Reus isn't that vocal, so that didn't help. Maybe the players don't believe in the coach or his system?? Maybe someone made them watch the last 5-0 game just before they played. It's just inexplicable that they were so frozen. All of them! And when it's not individual mistakes, or a couple players having a bad day, when it's the entire team sucking, then you have to look at the coach and maybe even the entire leadership.
How many other football clubs need to hire a whole team of sports shrinks in order to make their players perform in big games? Why would Dortmund have a group of players with such an unusually weak mentality? The answer imo is leadership at management and most importantly coaching level. Losing away to Bayern is always possible. Continuously getting thrashed in such a limp way is not acceptable.
Maybe not a whole team but sport psychology is common in tennis, rugby, fencing, basketball or any other Olympic sport, it's not a creative solution. I played hockey and a team psychologist who taught us how to regroup and react when losing or avoid mental fatigue when feeling physically tired late in the match. England under Southgate hired a psychologist to devise a penalty shootout routine that got them to WM semifinals and reversed their tendency to fail at spotkicks, their FA did not rely on Southgate to sort the mental game out. https://www.planetfootball.com/in-depth/tricks-sports-psychologist-uses-help-footballers-confidence/
You don't get the sense that BVB leadership has a particularly progressive mindset on this when Zorc is excitedly spouting in the prematch presser that the team just need to play "Männerfußball" in order to get the result. They recognized the value of having colleagues who have won it all, hence they brought back Hummels, but maybe they need someone on the sidelines transferring similar experience to the players. Who would be Dortmund's Zidane? Sammer?
Just came in my mind that Slavia Prague would make a better game against Bayern than we did. Maybe not better result, but for sure better display. They have far from our quality, but are coached to play without fear. The last game in CL, at home agains Slavia is definitely not won yet. Thought I’ll go and see that game (my first ever BVB), but after the match yesterday I lost my appetite