I think Nico Williams has a personal reason why he still chooses to stay in Bilbao. And it seems one of them is because his brother also plays for Bilbao. In addition, as you said, Nico Williams feels he has to contribute to the club that has given him a lot of playing time to become one of the young stars in the world. I think Nico will play one or two more seasons in Bilbao before deciding to move to another club. If he can consistently maintain his performance, there will always be a big team that will want to recruit him every season.