I see this whole event kind of like the Rosa Parks situation. I'm not comparing the magnitude of injustice, just that (a)There was an unjust system and (b)It took an individual to stick up for the just result, even though it was breaking the rules.
Also, the author is wrong in this passage:
From the article: "The gate agents offered offered $800 in airline scrip to anyone willing to deplane, which from past observation I think is the maximum that was allowed by United policy. That's an illegal cheapskate policy for which United fully deserves the condemnation it has received, and the fines it should be assessed for violating Department of Transportation regulations on denied boarding compensation. Obviously, the gate agents should have been allowed to offer more, and in cash, as Federal law requires. "
The truth:
The airline can try and get people to voluntary give up their seats with whatever method they would like. They can offer free kittens, cash, vouchers, etc. If no one accepts the airlines arbitrary amount, THEN DoT rules take effect, mandating the cash compensation amounts. So Dr Dao and the other 3 passengers that left the plane are entitled to a completely separate amount from what United offered.
From the DoT website[1]:
"DOT has not mandated the form or amount of compensation that airlines offer to volunteers. DOT does, however, require airlines to advise any volunteer whether he or she might be involuntarily bumped and, if that were to occur, the amount of compensation that would be due. Carriers can negotiate with their passengers for mutually acceptable compensation."
https://www.transportation.gov/airconsumer/fly-rights