Getting a striker like Haaland would be a miracle for PSG anyway. Things are not looking good at PSG at the moment. Especially after losing their important players, Mbappe will not be next year, so they will have to hold on tighter this year. This year may be better for PSG, of course, who will add to their squad during the interim transfer period, all will be shaped accordingly.
When it comes to Haaland he will have a release clause to be active next year. He will be able to be signed by spending 200 million euros if I'm not wrong. Haaland is also open to play for different teams throughout his career. Who knows maybe PSG can also try their luck with him.

But it depends on whether they will lose Mbappe next summer. Because for now there is still no progress on his contract extension. It won't be easy for PSG this time to convince him to stay longer. But they had better do their best because they are getting really weak without him for now.
As good as Haaland has been with Manchester City and Guardiola, I don't think he will be interested in leaving next season. He might be able to win more titles if he stays with Manchester City. Why will he leave Manchester City so quickly? Guardiola is also likely to be keen to keep Haaland in his squad. However, if City has the intention of selling Haaland, then they will not sell Haaland for less than 200 million. Haaland was probably bought by Manchester City for 60 million. They will be very profitable.
Mbappe is unlikely to stay with PSG. We are yet to hear any news about his contract renewal. And so Luis Enrique will definitely be looking for an experienced striker next season. I think PSG will benefit if he spends 200 million to add Haaland to the squad. Because PSG wants the title, money is not a big factor for them.