I'm sorry I have a strong aversion to hyperbole, but if you're going to compare the situations outlined in the article to slavery you're going to have to lump a lot of other stuff into the slavery pile as well. It's important to preserve the weight of words lest you further increase people's apathy.
I agree with this 100%. There are a lot of previously useful words that mean almost nothing today. "Slavery" is one. "Rape" is another. I know people think they're doing good when they try to expand the definition like that, but all they're really doing is taking away our capacity to describe things accurately.