A robot is as smart as the controls engineer. If fault detection and handling are lacking, I'd leave the blame, barring unusual circumstances, on the engineer. Our engineers are (a little biased here admittedly) the best in the biz.
That said, there are environments in which union labor makes more sense than non-union labor. Unfortunately, where union labor has advantages in long-term skill development, they seem to lack in work ethic. I'm not saying that this is universal by any means... It's just that the protection of the union provides a breeding ground for leeches that are impossible for management to remove. Maybe your experience is with a stricter union?
I worked in an environment similar to the one mentioned in the article through college. I actually did make more than $8/hr as the article suggests, so it seems likely that Amazon is under paying these people. But, the heart of my point is this: I work in a company that designs and implements automation solutions, and we'd barely be able to exist if it weren't for displacing expensive union labor.