Air travel certainly is not what it used to be like. Today, airlines do have the right to remove you from a plane, but they typically reserve that right when you are being disruptive or a safety issue had arisen.
Like when I was in process of boarding a plane from Heathrow, and I was at end of boarding line, and they held up boarding. Let us stand for an hour with security personnel passing us on gangway over and over again, before announcing they were deboarding the plane. And flight would be delayed. Waited 5 hours, but this occurred the weak after Pan Am Flight 103. As passengers, sitting in the lounge, we were grateful at the inconvenience.
Today, there are indeed reasons, but also ways to handle a paying customer. Perhaps United feels they make money being a courier (the things it carries in cargo area) and passengers are a secondary thought.
You know by now, and I have seen where the negotiations for oversold flights occur in the lounge area…not when passengers are boarded, seated and ready to depart the gate. I have been bumped from a flight, I have told checkin kiosk that I would volunteer and told them a $ amount, to have it taken up (no human interaction needed) and I have had another give their seat to me when I absolutely needed to catch a flight for dying relative.
From a customer service stand point, United does have competition, and while years ago I did receive good service from United, the service in my current region is subpar that I regularly choose to pay more to fly their competitor. And this is why, I got sick of getting stranded in a connecting airport at 2 AM for no reason at all and absolutely no empathy or information to be provided if I would be able to get a flight the next day, even if called their 24/7 customer service line and utilized my “VIP” account status.
In short, this incident was indeed handled extremely poorly. But it is indicative of a trend not just with United but others as well, but United is handling it worst of all, and is the slippery slope they have been surfing for awhile. United had options, they just do not have the culture in place to actually allow exploration of them. When an organization gets like that, they hemorrhage, and investors flee.