(I am a layman here so take this with a grain of salt) I believe you are correct, however no campfire will have enough airflow to get that hot unless you have a bellows or some other way of injecting air into it, and you'd have to have it structured in a way that it can efficiently burn the fuel. I'm not much of a blacksmith but had a friend who was into it and whose dad also was, and we did a pretty fair amount of "experimenting" as kids :-D I know from experience that elevation makes a big difference too, though I've never measured.

Would be fascinating for someone with knowledge of this to weigh in!