Look for it on Google and here is a list of the wealth of clubs in the saudi pro league, Al Nassr is in first place and Al Ettifaq is in 5th place but not sure about the legitimacy of the news https://www.totalsportal.com/list/most-valuable -clubs-in-saudi-pro-league/
One of the obstacles for players who choose the Saudi Pro League is that their national team career will be threatened, especially if the player comes from a country with many choices of players, Jordan Henderson will certainly face this if he accepts an invitation from Steven Gerrard. At the moment Henderson is still in the England national team squad for the European Cup qualifiers. If he goes to the Saudi Pro League, he has the chance that he will not become an English national player for the European Cup and of course that is not pleasant.
If Liverpool still keep him, then why move even though he is no longer the main choice for Klopp but that is a natural thing because he is no longer young, maybe in one or two seasons he will be interested because the money offered by Arab clubs is big and it will be fun in the end career can get a big salary so retire with a lot of assets.