If we talk about opportunities then indeed this could be a wrong choice when Ximons chose PSG over Bayern but when talking about money then of course PSG's temptation will be much greater.
Honestly looking at Xavi Ximons' posture, I personally don't see anything in him but when he plays on the field then we can see that posture and age don't seem to be an obstacle for him to shine because for this season his performance is getting more mature even at a very young age.

He shone at Leipzig but indeed in several statements he also said that if indeed he was still comfortable enough to stay at PSG so it was difficult to hijack him from this Paris club especially with the temptation of money and the possibility that his position at PSG would be more comfortable after Mbappe left then indeed the chance to stay was very high.

Now actually for Xavi Simons apart from Bayern there are several other big clubs that are said to be approaching him including two EPL clubs (Manchester United and Arsenal) but this is still just a rumor without any clarity.