Whilst dropping fares would be good for outbound travellers, the weak AU$ probably still can't help for affordability/conversion rates. In addition to yield, as a full plane on heavily discounted low yielding fares doesn't equal profit in the industry.

Will be interesting if the AU$ recovers in 2 years time. DL are taking the risk despite the Victoria State Government subsidy, gambling largely on inbound (US POS) traffic considering the weak traffic outbound (ex-Australia) due to the low AU$. If the AU$ is still slow or doesn't recover in time, MEL along with BNE could both see their DL services wrap up and conclude once the subsidies by their state governments start to expire.