He's always been hideously overrated so no surprise people are shocked it hasn't worked out for him and blame the club.
Nah, he was clearly extraordinary as teen and the hype built on that.
Over the years I noticed a clear pattern when it comes to people rating Götze´s time at Dortmund. The more times they actually watched him play there, the higher they rated him. The reason for that is that it made them aware of the reason why he was so valuable for them and what set him apart from other top talents. Götze´s biggest strength was not so much visible in single games but other longer spans of time. While he did not have a huge number of breath taking performances, he had only a handful of real offgames in over a hundred games.
In his three years at Dortmund, he never had a slump, infact I have trouble remembering an instance when he had two poor games back to back. The guy basically delivered every game and put on 7-9/10 perfomances like a clockwerk. That is why he always ranked so high in season long rankings as they value consistency way more than occasional miracle perfomances.
Such brutal consistency is already rare for players in their prime, but for a player in the middle of his development at 18-20 years old it was an absolute annormaly. After all consistency is the one thing talents normally lack a bit as they develop. That is why all experts promised him such a bright future. If a player has still room to grow in so many aspects but has already established such a strong perfomance level and lack of fluctations in terms of form, the way to become one of the best in the world is not that long anymore.
His downfall at Bayern was, that not only he failed to develop further as player, but he also lost the kind of consistency that made him stand out before. Instead of basically always having a clear presence on the pitch, he turned into a passenger a lot of time with some flashes of his old brilliance. It is like he regressed from the established top player he was at Dortmund to a mere talent with a promise of more.