Saudi Arabia knows how to play politics with FIFA. Just look at how they were able to lobby the AFC to have the Round 4 match held in their country, which gives them a significant advantage. Although the decision was protested by other teams because the match was supposed to be held at a neutral venue, the AFC still selected Saudi Arabia and Qatar to host the fourth round and ignored the protests from other teams. Because of this, I am even more confident that Saudi Arabia will qualify for the World Cup.
It has been known forever that Fifa and Uefa are both corrupted places. Fifa specially is a big corrupted space, they had to literally had their president go, just because he was bribed and it was ousted. So it's clear that they are on sale.
And if any nation wants to make sure that they get what they want, they can safely just bribe their way into it.
You still have to win the games on the field, even with all the advantage in the world, you can bribe the world to let Messi join you, if you want, if you suck, you suck, so you have to win on the field.
But yeah, bribery and corruption is a common thing for FIFA, they have been doing that for a long time and I do not think that it will end anytime soon and will help some nations more than others.