EDIT:
It looks like the bottom of the article explains that the US Consumer Bureau studied arbitration and found it anti-consumer:
As arbitration clauses appeared in tens of millions of contracts, the consumer agency was specifically mandated to study arbitration under the Dodd-Frank financial law in 2010. That effort culminated in a 728-page report, released in March 2015, that challenged longstanding assumptions about arbitration.
The agency found that once blocked from suing, few people went to arbitration at all. And the results for those who did were dismal. During the two-year period studied, only 78 arbitration claims resulted in judgments in favor of consumers, who got $400,000 in total relief.
It's not clear what the denominator on that sum is, though it is also stated that the rate of customers taking up arbitration was very low
The loss of class action status is terrible and enabled atrocious corporate behavior.