Lukaku is an excellent player but he have one BIG problem and is the drama he made in every team he goes, is incredible but he has something in his brain that make him feel uncomfortable or wants to leave, you can see it when he was in Chelsea and other teams, so he can have so much troubles in Saudi arabia i guess.
In fact, Lukaku is still very good in terms of performance, but because he often gets into trouble when he is with the team he plays for, respect for him among his teammates or fans is starting to disappear. We definitely remember the drama he caused last season when he didn't want to stay at Inter, even though the club owner had prepared fresh funds to make him permanent. But he instead chose Juventus, who were Inter's enemies, and the transfer also failed because Juventus did not reach the desired agreement with the player. In the end, Mourinho, who had also managed him at Manchester United, made Lukaku move to Rome.
I think this player is quite problematic and maybe if he gets to the Saudi league there will be something that will make this league bad in the eyes of the world in the future and that's why it's better if the Saudi league is still eager to bring in other European players, it's better to just look for other players who never had any problems with the club.