The only team who needed to show adaptability and flexibility last night was PSG, who knew they were inferior and had to sit back and counter. Bayern absolutely swarmed them. They had 31 shots and their XG saw them ‘beat’ PSG by 3 goals. Bayern must play this ultra high line because as you would have seen as well, aside from sporadic occasions, they win the ball back remarkably high up the pitch through sustainable but energetic high-pressing. That’s why they scored 100 Bundesliga goals last season and 79 this so far, and why they consistently hammer teams in the CL. If the game goes the same way in Paris, Bayern will turn this around. As many people have pointed out, last nights win by PSG was up there on the flukey scales with Barcelona beating Chelsea in 2009.
Also, your cited example of Pep is also...untrue, for lack of a better word. Pep has only been knocked out relatively early in the CL at City because he has adapted and been flexible. Starting with 3 at the back against Pool in 2018, rotating and playing with a 5 at the back against Lyon etc. Even against Dortmund, City we’re average, and we can even explain that by Pep wanting to try Bernardo Silva upfront and start with only one natural winger in Mahrez, leaving Sterling on the bench. Not the best example there.