Thanks. Interesting how rare and extreme these events are. This suggests a runway process is involved in that the fire spreads and multiplies in just the right conditions, but presumably it takes a while for nature to grow enough to become vulnerable to a large fire again? Not enough data here to tell for sure. It is interesting that some plants have evolved to require fire to survive and reproduce (pyrophytic plants), so wild fire is by no means unnatural. There does not seem to be a positive trend here.
I believe in recent past we've gone through: "everything's burning, let's put it out", "we've had massive fires, let's do planned burns", and now "let's defund organisations that can do effective bush management". This will explain some of the changes visible. The current area is due to the buildup nobody managed - neither by government organised burns, nor fire stick farming.
Yep this is exactly it. There is a periodic phenomenon going on here. We do not measure or collect data long enough to look at it like that. I think the trend is hard to spot here.