Dictionary definition of Robot:
"A machine resembling a human being and able to replicate certain human movements and functions automatically."
A golem isn't a machine. But it resembles a human (often), and able to replicate certain human movements (yes), and functions somewhat automatically (often requires instructions, but is able to follow vague-ish instructions, like "protect this person")
So I want to say that it sorta is, sorta isn't?
Mostly the "Machine" part of the definition.
Dictionary definition of Machine:
"An apparatus using or applying mechanical power and having several parts, each with a definite function and together performing a particular task."
Most golems use magical power, not engineering and clockwork, so they're not machines, therefore not robots.