I think there's a discussion to be had about the ethics of slavery when the slave actually enjoys it, rather than the argument we usually get, which is that slaves don't complain, express contentment in their lot, or that slavery is good for them even if they disagree.

We have an example of this, in d/s slave relationships. Two consenting adults agree that one of them will own and command the other and they will unconditionally obey. And some love it so much they fantasize about doing it 24/7 without safewords. And then the rest of the kink community has to gently lead them back to reality.

(I have a hypothesis this might be the same drive that motivates those rare women who are true believers in the tradwife movement. The obvious fantasy is that their husband will be a perfectly just master — although in the d/s version, the master isn't necessarily fair at all, but will punish the slave for missteps with sexy-time spankings or other erotic play — but the hazard of these relationships, full time, no guardrails, is that even with a well-meaning master, they get tired, contend with stress, and may even change with time.)

I don't imagine anyone profit-motivated is going to regard the wellbeing of their slaves in good faith, since they haven't historically, even their non-slave workforce, even when treating them humanely improves productivity and profits.