If the liberty someone is taking with the language is intentionally trying to manipulate how people think about something by abusing what words are commonly accepted as meaning, it's completely fair to call out that manipulation.
“The basic tool for the manipulation of reality is the manipulation of words. If you can control the meaning of words, you can control the people who must use them.”
― Philip K. Dick
It happens all the time that people chose their language precisely and in ways that clearly have more impact on another party's perception. Being pedantic over the definition of a word only distracts from what that word(s) is trying to do. I sense that you are really uncomfortable over what the word "wage-slavery" implies about the society you are participating in and are trying to cheapen it.
You're cheapening what slavery is. It's honestly pretty disgusting to equate serfdom to slavery. They aren't even in the same league.
Go read more about modern day slavery and then come back and try to justify comparing the circumstance of these people to those who are actually being treated as property by others.
> But language is malleable over time
If the liberty someone is taking with the language is intentionally trying to manipulate how people think about something by abusing what words are commonly accepted as meaning, it's completely fair to call out that manipulation.
“The basic tool for the manipulation of reality is the manipulation of words. If you can control the meaning of words, you can control the people who must use them.” ― Philip K. Dick