Actually some new PSG players like messi and Donnarumma have not been able to make a big contribution to PSG and of course that is a natural thing because after all they still need time to adapt at PSG, I agree with what you say because actually the main problem is PSG failure in the league champions is not because of players, but we can say that if Pochettino was responsible for the failure of PSG, we all know Pochettino capacity is not worthy to train a team as big as PSG and maybe we will see PSG rise next season in the champions league if they have a coach of the caliber of Conte, Zidane or even Pep Guardiola.
I think Pep Guadiola and Zidane are the two coaches worthy of handling big players, not all coach can handle big players, if Mourinho strategy and style of play is an attacking game, he would have been more suitable for the job, Psg had forgotten that Mbappe that's has been so consistent this season is due to the fact that Messi is assisting him, Mbappe won't be that flourishing if the likes of Messi and Neymar depart, if only Arsenal have the money and bid for Messi, his style of play will be easily adapted to Gunnerz
PSG only needs the right coach to deal with these star players, because without the right coach, of course it will make PSG continue to fail to win the champions league trophy even though they continue to bring in good players, mourinho, I don't think it will fit with PSG game scheme who is more inclined to attack while mourinho is a defensive specialist coach or bus parking so far.
If you look at arsenal's finances, of course they have the ability to buy messi, but the problem now is arsenal is not a priority club for star players like messi, of course you remember the reason vlanhovic failed to join arsenal even though arsenal was ready to buy and pay Vlanhovic salary with quite large, but Arsenal lack of a winning mentality is the reason why Vlanhovic rejected him.