The reason for PSG they spend lots of money but they can't get anything in the champions league is mostly because they didn't have a good manager and they just bought superstar players while PSG didn't have a balanced team, this situation made chaos in PSG that's why they players couldn't have a good atmosphere in the team to have good performance.
If that's true, it means that the main problem is with their own manager so that PSG can't do much in the Champions League, even though they already have more superstar players in their team. Because a strong team is not only good on the front lines, but almost on all fronts must be good in order to continue to compete in the Champions League. And from what I've seen so far at PSG, I think what you said is true because PSG played like they didn't have good tactics during the match.
Here we have too much talk about PSG and their tactics in Champions League which are not working, and they are facing problems which is surely needs to be fixed if they want to have better results they have too many stars with not good manager is also problem which create mess-up and players are not able to understand chemistry of the game too much interference from the management is also problem but now as they have very good and experienced manager and big stars are also left this club hopefully now its good time for them to have understood all things and allow new coach to work with his strategy which bring good results and improved performance.