Messi is back in form and he gets along especially well with Neymar. This season, Messi contributes to the score, sees the fine passes, makes a serious contribution to the team. These are what PSG needs, the team's offensive power is high, but they play messy. More PSG players than opponents are fighting for the ball with their teammates.
Messi is one of greatest players in history but he is more humble, more professional than Mbappe. I think the professional and love for football with help Messi to have a better performance in his second season with PSG. After a first adaptive season with limited contribution, I believe Messi will have much better one in this season.
Especially Mbappe has been extremely selfish in the last few matches, he doesn't pass, he doesn't pass to his available friends etc.
If it goes on like this, a middle class team playing solid team games will eliminate them in the champions league before they can go far.
Mbappe is going on a same bad journey Neymar did seasons ago. Mbappe now is like Neymar in the past and if he won't change, he will get nothing in next few seasons at his 30s. Neymar had a same conflict with Cavani in first 2 seasons after moving to PSG and now he has yet achieved anything big with PSG and for himself.