The Saudis bought loads of top players but no one cares because the overall quality is still crap due to not producing any domestic talent. The same thing happened in China.The Prem is most popular now internationally because our clubs are the richest and can buy the most expensive players. But as the American game grows domestically, their clubs will get richer and richer, and they will eventually start competing with European teams in buying the best players. When they can afford those players, then the international interest will grow. I see kids already in my local park in Shirley wearing Inter Miami shirts.
And the US is producing lots of talented players now. Even if it is their fifth or sixth most popular sport, there are still millions of genuine football fans in the US.
If they have a successful World Cup - which they will - the game will become even more popular over there.
The MLS will become an elite league. Not next year or even five years from now. But twenty or thirty years down the line, it will.
You need a combination of wealth to buy talent as well as domestic talent coming through youth set ups (Europe also has advantage here too as players can move abroad and be a couple of hours from home rather than 10 hours+).
The mls and Saudi will never compete with PL or even the other top euro leagues