Your description actually illustrates how terribly inaccurate the metaphor was. If enslaved people imitated the people who enslaved them, they'd be sitting in a rocking chair on a porch sipping lemonade.

The US has a unique and relatively recent relationship with chattel slavery so people are more sensitive to it now.

The earliest record of the master/slave terminology being used in engineering is 1904 by which point slavery was already outlawed in almost every country, including the US. You're right to say that chattel slavery in the US was a uniquely grotesque form of slavery, but there is no system of slavery in history where slaves are primarily imitating their masters. No matter what anyone's sensitivity to the topic is, it's a bad fit for what's being described.

It sounds precisely as edgy as I thought. Supervisor/grunt. Yodel/echo. I offered one with whimsy and another without as much edge.