Asensio was a quite promising player when he was young. But he couldn't meet the expectations exactly honestly... His real downfall happened after joining PSG where he couldn't find much chance to play. 
He is still a skilled player of course. But I doubt he deserves such a high salary. He makes 14.5 million euros a year at PSG and now he is still expected to earn 10+ million at Fenerbahçe.
It's a bit unfortunate for Asensio at the moment, he's one of the players I quite liked especially when he was at Madrid but there are indeed some things that make his performance slowly seem to disappear even though his condition was initially quite good.He is still a skilled player of course. But I doubt he deserves such a high salary. He makes 14.5 million euros a year at PSG and now he is still expected to earn 10+ million at Fenerbahçe.
Losing the main place in Madrid seemed to make a little momentum in the growth of Asensio's performance lost and his mistake for me was moving to PSG but could not develop there.
Now Asensio is looking for a smaller club even though it's good especially Fenerbahce is also not a small club for Turkish size but I remain
Now Asensio is looking for a smaller club although that is good especially since Fenerbahce is also not a small club for Turkey but I still regret the little career he has had.
I quite hope he regains the momentum to make his situation better especially for performance size but it comes back to Asensio himself in the end.
What I noticed in the last few years is that there are now more exit options for players and they are much faster when it is about signing contracts with one of those smaller teams because they now can offer lucrative contracts. Usually signing a contract with a team like Galatasaray meant that the players have to forego a significant amount in salary, but now these teams somehow have more income or financial resources at their disposal and as soon as they are willing to pay enough, players are willing to give up their dreams, like fighting against the competitio in Madrid, much faster and then they end up in a league like in Turkey.