If what UA did as far as randomly choosing 4 people to exit the aircraft, what do you believe should have been done with the passenger who refused to leave the aircraft?
It should have never gotten to that point in the first place - they made a huge error and compounded it with the forced ejection.
If you're at your local diner counter, have just started to eat your breakfast, when the manager tells you that you will have to leave the diner as one of his employees wants to sit there and eat your breakfast.
When you refuse, two thugs grab you and forcibly toss you out of the diner.
And you would be OK with that?
They should have kept upping the money for the voucher. Do you think people wouldn’t have volunteered for a $2000 voucher.
Right there is your problem. That is not how they should have determined who got booted. Everything the airline does from overbooking flights to transporting staff around the country on their planes is associated with a cost/benefit. Part of the "cost" of doing these practices should be the fair market value of the seats they taking away from people who they have already made an agreement with. The people who gave up their seats should have been the first 4 people to accept their reimbursement offer.
The whole idea of a free market sale is that I have federal reserve notes that I assign a certain value. You have a plane ticket that I assign a certain value. I make the judgement that the value of your ticket is worth more TO ME than my federal reserve notes so I trade you. You make the judgement that my federal reserve notes are worth more TO YOU than your ticket so you trade me. After that transaction is complete you shouldn't be able to re-evaluate and say, "You know what, that ticket is now worth more TO ME than I initially thought it was worth. I want to cancel the trade."
That isn't right. If they want to acquire the seat back for some business related purpose, they now have to make me an offer that is worth it to me.
This isn't the same as removing someone who has violated the rules. If someone is not living up to the agreed upon behavior requirements, they should definitely be able to be removed.