The problem with the PSG team wasn't about the poor management of the team because the management brought in good number of players to help solidify the strength of the team but they failed because at some point the players wasn't having a good relationship with each other on the field.
The Manchester City team is a typical example of a team that made good use of their money to get what they want because they got a good manager who got quality players that has helped the team to win the trophies they wanted, I think the problem that PSG has for not winning the UCL with the presence of Messi, Mbappe, Naymer and Ramos was bringing the stars when they were not in their best form.
One of the problems you mentioned was really visible at PSG apart from the perhaps less than harmonious relationship between the star players who were already in the PSG squad at that time. However, everyone also sees other things, such as the age of the star players who are no longer the same as before when they were at PSG and also the easy competition in Ligue1 for PSG to win the League every season. So that the players' skills and enthusiasm do not develop when playing in the Champions League.