The UEFA is so far ahead that no matter what they do in the Asian area, they won't close the gap at all for the next five decades. Only if a dozen states decide to take tons of money and pimp their national leagues. But they would still have to convince South American and European players to go there. It's not enough to get some almost retired players like Ronaldo and some money grabbers. They would need the next Messi, Mbappe, Modric, Zidane, Robben, Ribery, Maldini, Buffon etc. That's when people from all over the world would start watching those games on a regular basis. Now it was only short term hype because of Ronaldo.
Saudi Professional League are building and it's not true to say they will fail. They need to do more especially things in youth academies to grow up their home grown talented players who will be future of the league and their national team. If Saudi Arabia can invest into their youth academies better and in long term, they can get massive success like Japan. We knew that Japan started their ambitious plan with a Brazilian player Zico and after about 3 decades, we can see how their Japanese League 1 and Japanese player quality are now. Their league is one of best, or can say the best in Asia continent and Japanese players now can play at world class level and are key players in big clubs too.
One of the best in Asia, but not at all comparable to any European league and do you know what great Japanese talents do? They leave Japan. They play in Europe. The charisma the European top leagues have developed over time will ensure that the best players in the world will go there.
It's like the NBA. Of course other countries can try to invest in basketball, but do you really believe that American top talents will start leaving the United States when they have the chance to play there? You are talking about youth academies, but it is not enough for Saudi Arabia to do it. You need international competition because that is what the people want to watch and what the players want to achieve. The Bundesliga couldn't be as great without the top leagues from other countries. You can't turn Saudi Arabia into one of the best leagues in the world if other Asian leagues aren't also the best leagues of the world.
If a Japanese top player wants to play with or against Mbappe and Haaland, what is he going to do? Hope that Mbappe and Haaland go to Japan? It is more complex than just shoving money into a national league. The UEFA is an empire, and the countries are cooperating castles and the competition is a deal they make in order to offer the best product to the people. But you know, people will keep believing that buying retired Ronaldos will turn the Saudi Pro League into the new centre of attention. Pretty funny.