Doesn’t change the fact that the society has laws build on ancient superstition without reason.
A society build on primitives rules that follow such rules is primitive per definition.
Because the practice of such primitive laws guide all activity in a society.

What about death penalty to the victim is not primitive and barbaric?
How is a society that execute primitive barbaric laws not primitive?
Is it because they can make nice cookies?

How does this complexity you mention change that it is a primitive society?
Is it because it is not PC to call a culture primitive? Because then I’ve got news for you, some cultures are very obviously more primitive than others.