Any court forces an adversarial resolution: the parts have failed to come to an understanding so they are investing in a legal battle from which the loser will come out bruised, having wasted money, time, prestige etc. A strongly negative-sum game.

The ease of which you can go to court can motivate parties to use it as a strategic threat even if they feel they don't have a particularly strong case, and the openness of the court system can make that small chance of success a strong threat against a public person or company.

So arbitration, by definition, can find a mutually acceptable solution with a zero sum, as opposed to the negative sum of a legal war. Society stands to gain if arbitration works - but not in cases such as these, were forced arbitration is employed as a stopgap against any and all claims.