The decision held that Gruden could proceed in court rather than binding arbitration, which is a nemesis to plaintiffs. Arbitration agreements are unenforceable if they are procedurally and substantively "unconscionable," meaning that the arbitration clause offends notions of justice and fair play. The arbitration term is procedurally unconscionable since it is a provision that the NFL demands be put into every employment agreement for NFL teams and is therefore not negotiated, meaning it is a contract of adhesion (forced onto the party with lesser power). As to the substantive unconscionability, the NFL's problem with their arbitration provision is that Gruden was no longer an employee of the league when he filed the lawsuit so the arbitration term would not apply according to its own language (i.e., that all claims by employees must be litigated in arbitration and not court).
Not only that but the final arbiter of any claim against the league or its employees would be Goodell, so if the arbitration term were enforced, then Goodell would decide the fate of Roger Goodell. The only inexplicable part of the decision from the Nevada Supreme Court is how two of the seven justices felt that the arbitration term was conscionable, i.e., fair, where Goodell would decide the fate of Goodell.
Gruden would have been allowed discovery if the case had proceeded via arbitration so the emphasis on discovery is not really relevant. In fact, arbitration terms which limit discovery are generally deemed unconscionable. The issue is that arbitration is so grotesquely slanted in favor of defendants that any plaintiff seeking damages is trying to overcome a massive bias in favor of the defendant. That is the case since the party who places the arbitration clause into an agreement is obligated to pay the cost of the arbitrator since all a plaintiff would need to pay to pursue the case is a filing fee. Arbitrators get paid $100,000 or more for trials and thereby have a huge bias in favor of the party paying them for the simple reason that they want future cases and if they slam the defendant, guess who never gets another $100,000+ arbitration referred to them?
State law cannot prohibit arbitration since Federal law recognizes a right to arbitration under the Federal arbitration act. However, arbitration is no longer allowed for sexual harassment cases in either state of Federal lawsuits under a 2021 law, 9 U.S.C. §402. That statute was passed after a series of well-publicized sexual assault cases involving US Army personnel were forced into arbitration rather than via the courts.
