I wonder if Messi declines an offer from PSG because they don't want to pay him enough and he has to accept salary cuts, how is Barcelona going to stem the salary for Messi? That is the part I don't get here.
If Messi is going to decline PSG's offer of a new contract, i don't think it is ever going to be bacause of the money they are offering, PSG has enough money and they are paying Messi very well, i think Messi might leave because he feels unwelcomed, especially by the fans who have booed him a couple of times, both this season and last, thus Messi might go to a club that adores him, and there's no better one than Barcelona.
Having said that, i don't quite understand the situation in Barcelona, they let Messi go because they are broke and then they start buying many players with a high salary range/scale, and now they want to bring Messi back, how do they now intend to pay him.
There were rumors that PSG also wanted to cut his salary because they are afraid that the same might be happening to them as it did to Juventus Turin. Since they also have to take into account that players like Neymar or Mbappe could be leaving, they would have to find replacements at the same time.
But yes I agree, money probably won't be the main issue. If Messi thinks that the fans suck, he could easily leave and go elsewhere. His relationship is not and will never be the same as it was with the Barcelona fans. But still I wonder how Barcelona would ever be able to pay his salary.