It’s not a direct answer to your question and I don’t have a reference to hand but I found it interesting. I read that the 74-75 fires were a fairly different s

It’s not a direct answer to your question and I don’t have a reference to hand but I found it interesting. I read that the 74-75 fires were a fairly different situation - the year before there was anomalously high rainfall which lead to a large amount of unsupportable grass growth. The grass grew over a huge but primarily uninhabited area, died, and dried out. When it caught fire the next year it was allowed to burn uncontrolled. So it was primarily grass being allowed to burn in remote areas versus the current situation which involves more forest and is being actively fought.