Industrial robots are not usually like human beings in any way. They’re not distinguishable as having a race, class, or caste. 
It doesn’t usually matter what color they are, and they’re not subservient or dominating — in fact, these questions don’t even make sense for industrial robots.
For service robots, social robots, and even some cobots, these questions can matter. Some observers of technology claim that most humanoid robots look like white people. We’re not completely convinced of this.
Some service and social robots look like women, even having completely meaningless bosoms and makeup. Some observers say that the femininity of these robots is intended to make them seem subservient.
Waitress and nurse robots could certainly fall into this pattern. Quite a bit of research has been done on the effects of using male, female, or nongendered voices for speaking robots.
Dialect
Now some researchers are wondering about using different dialects for robot voices.
The research, conducted in Germany, compared robots speaking in “standard German” with others speaking in “the Berlin dialect.” The researchers specifically wanted to know the effects of having a robot speak “in dialect.”
We admit that we are a little bit perplexed by this. Everyone speaks a dialect, just as everyone has an accent. We don’t really know whether the Berlin dialect has higher or lower status than “standard” German, or how meaningful “standard” is when talking about the German language. We know that back in the old days, people contrasted “standard English” with stigmatized dialects. That might not be what’s going on in the German experiments at all, but the researchers’ comments did suggest that standard German has higher prestige.
What did the study find?
Broadly speaking, the standard German speaking robots were judged as more competent and more trustworthy than the Berlin dialect speaking robots.
People who said that they spoke the Berlin dialect well themselves were more likely to score the Berliner robots higher, suggesting that there is an in-group/out-group judgement going on.
Would people from the American South prefer a robot with a Southern drawl? Would Midwesterners find a robot with a Midwestern accent more trustworthy? We’d be interested to see.