You don't think you'd be able to dredge up similarly bad stories for any other airline?
Look, what United did on that flight was pretty awful. But the rest of this to me smacks of the typical rumor mill that spins up when a company has bad PR, which surfaces the typical sort of 2-deviations-below-the-bell-curve scenarios you'll occasionally have when you're a company at United's scale - a scale that employs tens of thousands of people that do not actually all act as one giant United hive mind as much as we'd like them to but rather each as autonomous people that can occasionally do wrong things in a way that has no bearing on the company at large.
(That was a pretty long sentence.)
For what it's worth, I know an employee of United who loves it. But what was that saying about the plural of anecdote again..?