A few years back hen I was in Army Aviation, I remember reeading somewhere that the FAA won't mandate an AD unless it will cost less than the comparable number of lives it will save, and placing a value of $1.8-ish Million Dollars (US) on your average person.
Ie, AD costs $100M to implement, but will save 20 people, no go. But if it will save 50 or more, then it will be mandated. No idea if this is accurate or not, but no matter...
Taking that figure a little further, with over 100 deaths so far, and a CL-415 costing around $35M AUD, I sincerely hope questions are asked as to why we don't have our own fleet of these aircraft.
Use them for SAR in the winter months, or send them to North America and make them pay their way, but for gods sake, we need something like this...
Thankfully we're in NSW and completely safe, but having over 100 people die due to a bloody bushfire isn't good enough anywhere.