Seems apt to me. Indentured servitude actually seemed reasonable to a lot of people looking to move, you got expensive passage on a ship in exchange for working for a set length of time. Facebook is a platform for social manipulation, in a few hundred years I wouldn’t be at all surprised if we see that social manipulation as a morally intolerable evil. The sort of tracking/aggregating they do is a violation of privacy as extreme as indentured service is on free will.

An analogy is not a comparison. I think an analogy here was made to reinforce the point made, not to in any way claim that Facebook somehow deals with indentured servitude.