United in particular and airlines in general have been a costumer-hostile industry for many years. Probably since the advent of cheap fares. For an industry that is largely protected and even funded by the government (and hence the tax-payers), this attitude is ironic and depressing.
The consolidation in the industry has largely killed competition and the number of airlines available to take you from one place to another is usually and practically just one. The current outrage will boil over and those claiming to never fly United will quickly change their minds anytime they are confronted with higher fares or long flight durations.
The modern business world is dominated by oligopolies and we may have options but no real choice.