The World Cup's value is derived from the players, not the other way around. The Saudis as stakeholders, for example, could finance a football tournament of teams based on their nationality open to all players, regardless of league affiliation, and in one fell swoop rob FIFA of its primary revenue source. Currently the legalities of doing such a thing would be questionable, but likely unstoppable. If FIFA excluded certain players from their tournament, they would have no legal ground to defend.
And people would rather watch Harry Kane play for England, Neymar play for Brazil, Messi for Argentina, etc. than a bunch of 2nd Div non-ESL players.
Fooling yourself thinking the WC is a roadblock. How easily it could be replaced is precisely why UEFA and FIFA will go along - they risk everything, their very existence, by drawing that line in the sand.
Your second paragraph basically admits that - the PGA tried to stand up to the LIV, and eventually folded because they realised it was surrender or death on moral principle.
Again - you make all the arguments against your own assertion, yet somehow fail to realize it. I'm left to wonder where your typical rational mind is at.