At left wing Neymar, at right win Salah, at behind striker Messi, and a decent level striker (not even like Haaland, just a good one is enough) would mean that they would be able to use Zidane to win UCL. I know it wouldn't be easy, but they will certainly be doing better under Zidane than how they did with Pochettino.
They have money, they have highest paid players in French Ligue 1. Top most are Neymar, Messi and Mbappe respectively. Mbappe is the third most highest player at PSG, however he is the most focused among them. Waste off money exception of Mbappe is worth it, but can they retain him? He can be paid more only if stay at PSG however nothing is permanent. He could leave, yet they should need to supplant him with a quality striker. Till now, all that money for nothing. Recently lost at Bernabéu and their dreams to win Champions League trophy disappear. Best substitution is here the only solution, under best coach. Pochettino have not any more opportunity.