[Tenhundfeld]

Yeah, I hear that. I think the general point still stands. Master/slave is a metaphor that we have imbued with specific technical meanings in certain contexts. However, it is rarely (probably never) a perfect match with the historical meanings of slavery. We now have equally precise, typically more precise, terms we can use instead of the metaphor and avoid the negative baggage recalling barbaric acts.

EDIT: Not that you're arguing otherwise, I'm just restating my point more succinctly and abstractly.