It’s worth remembering that arbitration is actually a common enough practice outside of employment. Any divorce involving “mediation” is arbitration, and both parties agreed to it. The disconnect comes when the person “suggesting” arbitration (the employer) is in a position of power.
If mediation is unsuccessful, neither party has lost or waived the right to a court appearance, so your analogy doesn't hold. Mediation in divorce is a cost-saving measure often required by the court.
That's a very valid point. That's why I think employer (or TOS) mandated arbitration are ridiculous. I should have the option of disputing the arbitration result by default, but many clauses say that the arbitration result is binding and that you have no other recourse.