But they're not introducing nuance, they're invoking FUD.
Their arguments aren't, "RCV is way better than FPTP, and it's great that communities are adopting it, but I happen to like this similar system even better. Let me tell you about it." I would love to see discussions like that.
Instead, their arguments are "RCV bad. [Other system] good.". Their arguments play right into the hands of those that want to delay/avoid change so that they can continue to manipulate elections.