Dao got minimal $ for being dragged. Most of the money was for serious injuries he suffered when United unnecessarily placed him at risk. Believe it or not, it’s possible to deplane a passenger without putting him/her in the hospital. Dao still needs reconstructive surgery. Most passengers would consider that level of personal injury too high a price to pay for an eventual settlement.
In other words a consequence of his resisting their efforts to remove him.
Look, once they've sent two big guys with clubs or tasers to remove you, you are going to get removed, and you have to be some kind of moron to think it is not going to turn out badly for you if you resist.
Once the big guys showed up he should have said "Okay, Okay! I'm leaving. "
Trying to stay in the chair when it is clear they have the muscle to remove you is just stupid.