It's generally a pretty neutral term but it can also be used as a pejorative. I've seen videos of people screaming "You're a cis white male!" and they were absolutely using those words as slurs. It all boils down to context and tone really.
I don't think that's what they were saying. I think they were expressing their race, sex, and gender based hatred of another person. To me that makes it a slur or something so similar that the difference is irrelevant.