From PSG crushing defeat today, I can conclude that underestimating the opponent before the game is the biggest mistake. We can also see that the PSG players were unprepared for defeat. A string of wins made them forget that there will always be losers on the pitch. Their mental state became uncontrolled, leading to rough play and even committing unnecessary fouls.
Even though the match was over, the heated drama ensued, but this reflected PSG lack of mental preparedness for defeat.
Congratulations to Chelsea, above all you deserved to win.

PSG players probably did not take Chelsea really seriously, this showed in their performance in the early minutes of the first half, they began to put in the effort in the second half when Chelsea was already fired up and was very much ready to get the game to victory, if they had gotten a goal in the first half, chances are that they would have been able to get the game to an equalizer and move to extra time and secondly I think PSG players have been stressed, giving all their best in all previous games to this point and also considering how they played the UCL to the finals and not long enough the Club world cup kicked off, so they may have been fatigued for this game, anyways congratulations to Chelsea, the new world champions.