I think the point should have more nuance. Nobody looks at enron's abuses and says corporations are blanket bad (okay, many do, but not most). Nor do they say enron's abuses were fine because corporations as a whole benefit society. Most look at enron and say corporations have the potential to do good or bad, so let's figure out how to keep them from going bad.

It's not unions good or unions bad. The focus should be on how to get unions that don't lead to the abuses people are afraid of. When it comes to unions, the discussion seems to be much more take-it-or-leave-it.