You are right, if great players like Ronaldo and Messi move to a Saudi Arabian club, it will definitely attract the audience there and increase the interest for Messi or Ronaldo fans to watch the matches of the club that has been chosen by this top player club.
Messi and Ronaldo I think these two players will get better and have a perfect career in a Saudi Arabian club.
Now that Messi is in the MLS, it is interesting if the club from the Arab league could attract Messi before because it is the same as creating conditions where they will make their popularity rise rapidly and indeed now it also happened to Inter Miami when Messi arrived just like Alnassr last season who arrived Ronaldo.
In a short time Inter Miami's social media immediately boomed because of the effect of Messi and now they already have 5.9 million followers in just a few hours of Messi being reported there.

However, when an extraordinary player comes to a club that we haven't even seen play before it will be very curious. At least this is also in addition to benefiting Messi with this large contract also benefits the club and the league itself because their prestige increases dramatically.