I'll say this...anyone who's ever been in a courtroom knows not to make absolute statements. The GOR is just like any other agreement, it can be challenged and litigated. It's a powerful deterrent.
The enforceability rests with 1) A judge, and 2) The other conference members will.
I don't think anyone is leaving their conference, but the opinion that GOR's are invincible bothers me.
A GOR can be challenged and litigated-if someone wants to do that.
But there are also consequences of taking such actions.
One can look at real cases to see what sort of outcomes there might be. Such as Maryland leaving the ACC.
In that case there was a buyout increase Maryland didn't vote for. Still, Maryland had to pay over $30 million in order to get out of that agreement. While the court case went on--in the two year neighborhood, Maryland didn't receive revenues from the ACC.
A grant of rights is a much larger animal in that it involves much greater revenues, and there is a carefully evaluated and signed documentation giving media rights to a conference for the duration of a contract.
So if you are Louisville, OU, or whoever, you are trying to get back something that no longer belongs to you because essentially you changed your mind--knowing that while you may be successful in part, your probably going to still end up forfeiting $60 percent of that. When you are talking about hundreds of millions of dollars its an impossible amount. And that is one part of the financial hit. The other part will be the conference buyout where you'll also have to pay tens of millions of dollars.
So you'll have court fees, loss of revenues for years, the new conference won't be able to make anything off your media revenues, but will have to pay you more than you made before to A: entice you to leave in the first place and B: make up for all the lost revenues you are going to take on for years. Also, there are going to be legal issues with any network which pays the media rights revenues to sort out in court at huge expense.
A conference trying to acquire a school under a GOR would have to fork out hundreds of millions of dollars and yet somehow still keep their existing members from losing money, even though there's no new revenues from added members for years.
All of that doesn't take into account the voiding of networks tv agreements and all conferences grants of rights which could cause massive destabilization around college athletics and television partners alike.
So, yeah, someone "could" take a GOR to court, but no one involved in the business expects that anyone will, and certainly no conferences are going to try to challenge one.
The idea that GORs are some easily breakable deal that can or would be done is not taking the reality of the situation into account.