It would make an interesting case..except I don’t think we will get to see it.
I think UA will settle.
They most likely will. I hope this guy gets a good lawyer; he'll need it. United's got a slew of amoral corporate attorneys and it will be a David vs. Goliath battle.
UA doesn't need to settle. They didn't do anything wrong. They were within their rights to bump those 4 people of which 3 complied and this drama queen didn't so the captain or the crew under his/her direction called airport security to remove the offending perp who refused to leave. Getting off that plane was not an option for him and due to his obvious to us now mental health problem; he was forced to leave.
He only had two choices at that point. Walk off the plane like a man or be dragged off like a screaming toddler. He obviously chose to act like a toddler and was treated as such. In the future they may start using knock out darts or something to subdue difficult passengers with full legal authority and no chance of being sued for it because of unruly unreasonable passengers like this.
If the airlines didn't have a lot of discretion on how they run their operation to get thousands of people per day to their destinations; ticket prices might be double or even triple. This is why they can overbook and also because it's not common for everyone to show up for every flight so some seats may go empty while some other passengers are waiting to go on a standby basis.
In this case the airline got a late notice of needing a flight crew at their destination so another flight with maybe hundreds of people would not be delayed.