Another story on the front page right now[0] from the WSJ[1] seems to imply that arbitration clauses fall apart when faced with a mountain of arbitration demands (75k+). Amazon is now seeking to remove its own arbitration clause for customers so that these can be consolidated into a class action lawsuit.
[0] https://news.ycombinator.com/item?id=27356550
[1] https://www.wsj.com/articles/amazon-faced-75-000-arbitration...