No, I think it's nitpicking because it truly is in some cases. Science communication is about simplifying things and making shortcuts while keeping things engaging. Of course Sagan didn't go into a tangent about the first use of the word barbarians or whether ancient greeks would define robots the same way we do. That's pedantic.

There are a few good examples of significant errors in the link I cited which I think are substantial - the portrayal of Hypatia is a big one. I just wondered whether there were more discussions about other history topics he got wrong, since you yourself mentioned that "almost every single thing" he said was wrong.