To be honest, I didn't saw anything related to Neymar to Chelsea last transfer window. I mean its not even close. IIRC, Neymar 1-2 years ago signed a long contract which expires in 2025 and has option to extend further. So I don't think PSG has any intention to let him go Neymar has any plan to leave the French giant.
I don't think Chelsea will make a bad decision to sign Neymar. Chelsea management is not stupid. There is no doubt that Neymar is an excellent player. However, Neymar is not suitable for a competitive league like the Premier League. Neymar's fitness is not good. Although Ligue 1 is relatively less competitive, Neymar cannot maintain his fitness. Neymar missed most of the season due to injury. I don't think Chelsea will add such a player to the squad. Chelsea will definitely want to bring in a young player next season.
You are right. Chelsea management should learn from their mistakes. They sacked Thomas Tuchel. The new coach cannot improve the team. They have recruited several star players, paying high wages. But still, their performance is poor. Signing Neymar would be another bad decision for Chelsea. Neymar's fitness is not suitable for the Premier League. However, Neymar's move to Chelsea was purely rumoured. I would say that the chances of this rumor being true are very low. Perhaps Chelsea will try to bring in a young player.