Van Dijk is Liverpool's main defender. Saudi League will be popular because of another top player like van Dijk. More players will join the Saudi league, as teams offer big salaries for them. Some of these players prefer to stay in Europe.
Saudi league is already popular with the number of players that joined last season so what more will a player joining will add. Van Djik is a a very talented player and also experienced and joining the league will be a massive boost to the league and the team he joins but the question is, is Liverpool ready to let Van Djik go?
They have lost Kloop already so if they lose Salah and Van Djik this season Liverpool may go back to being a normal average team in the league and challenging for the title maybe difficult.
Saudi teams are known for offering a lot of money to players and that way it will be difficult to turn down their offers especially when the player has limited time to play for.