I read the article in the Post. One worker mentions how the stock he got as compensation had been worth $95,000 and is now worth less than $5,000. He's already lost so much the last $5,000 doesn't make much of an impression.
That's the problem. The morale (or confidence in management) is so bad that they just don't care anymore. Rightly or wrongly, the view is they gave in for years waiting for things to get better and it didn't. They'll keep working until they don't have a job anymore, then they'll find something else. Maybe with whichever airline fills the gap. Maybe not. Maybe they will be making a lot less elsewhere, but they don't want to give that money back to United.
I know not everyone feels this way, but when you have so many willing to express this view to anyone who asks, it's not a good sign.