Wunwing...
If it's ...
(a) affordable.
(b) cost-effective.
(c) more of (b) than the other available options...
Then undoubtedly it will be examined.
In reality, bushfires in Australia kill an average 5 people per year.... the majority of which would not have been saved by your solution, but which may be saved if we get more fundamental things right, like fuel management and education.
It's the politicians who favour big-ticket items. The people on the ground would often rather have their 25YO, petrol-powered truck replaced with something more reliable.
I can't emphasise enough that in the fire management "market-place", aviation competes for limited dollars. There are a lot of other needs.
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That said, it is a conviction of mine that we NEED more Fuel-Reduction Burning. Every major inquiry since 1939 has said so, yet the Land Management Agencies seem to have an institutional nervousness on this subject as they get carpeted every time one gets away. Even if the "damage" is minor. Having a larger aviation presence and budget may help them acquire the needed courage to do the work.
Peter