PSG is currently looking for players who have higher talent after Mbappe left because PSG is worried that when Mbappe leaves him his performance will definitely decline so PSG is trying to bring in Julian Alvarez even though I think this will be very impossible.
Coming back to Manchester City, if they are tempted by the big offer from PSG and won't have a problem with Julian Alvarez leaving, that could happen but the only question is whether Julian Alvarez wants to risk his career with PSG who will forever be the rulers of League 1 without being able to win a title better.
PSG can offer Julian Alvarez a big salary but the problem is what about his future career? Julian Alvarez is a talented young player playing in one of the most competitive leagues in the world. If Julian Alvarez chooses to move to PSG then he will be able to win the Ligue 1 title but I am afraid his career will decline. Not many people watch Ligue 1 compared to the EPL. This is the same as what happened to Donnarumma, whose career is no longer in the spotlight because he chose to play in the farmers' league.
There is no doubt that Paris Saint Germain can meet the large salary that the player wants according to the agreement, they are a team with a very good financial situation, so spending a lot of money on the player's salary is not a problem for them. They have even done it to 3 players at once, Messi, Neymar and Mbappe, they spent a lot of money on these 3 players and it didn't cause them financial difficulties.
But what you say is true, Julian Alvarez is still 24 years old and with his good performance he can find an even better team. In Ligue 1, especially when he was at Paris Saint Germain he wouldn't find tough competition and I don't think that's good for a player. Because no matter how good a player is, they still have to face tough competition to keep them from being in their comfort zone which ultimately is not good for their career. If Paris Saint Germain wants him, then he should consider not accepting the offer that comes.