Reportedly, Messi has no intention of extending his service with PSG once his contract expires. he has stated this on several occasions, when he was interviewed by several sports media. it seems that Messi will not be with SPG next season. however, it is possible that the decision may change depending on the situation.
Because of that, PSG are rumored to be signing Aubameyang in the next transfer window as one of Messi's replacements.
at least, that's how the rumors developed regarding Messi and Aubameyang.
If Messi returns to Barcelona. I'm sure the salary issue will not be an important issue for him, he has everything, but if he returns to the Camp Nou. maybe he wants to end his career as a Barcelona legend.
I personally really hope that Messi can still be at PSG at least this will not interfere with the club's financial condition when compared to Barcelona.
But until now the contract extension does not seem to be going well.