The only way this could be economical into Australia would be if it had an energy storage capacity. Someone might do the math and build a battery to be powered from this and inject into one of the grids, but longer term, if it is to supply singapore, it makes more sense to put the batteries at the singaporian end.
https://opennem.org.au/energy/nem/?range=7d&interval=30m
Maybe power from further away could help toward replacing the base power. A little more sunlight for the east coast peak. Less chance of a cloud or a still day on the east coast causing an issue like Callide coal exploding the other day. Yeah it is a stretch (literally thousands of kilometres).
If we're being ambitious, I'm excited about off-shore wind. If end game for NEM is 2/3 wind and 1/3 solar (with storage/hydro/gas in single-digit percentages filling the gaps) there are many inevitable projects and growing pains to come.
SG is wealthier and also burns quite a bit of natural gas (demand is roughly 6-8GW constantly [1]).
[1] https://www.electricitymap.org/zone/SG?wind=false&solar=fals...
Finance is highly conditional on the sale of the power, but the power can't be sold until the project is complete for the long-haul subsea HVDC cable. So the capital works have to be done to completion before any income (not entirely unusual, but it stands out there is little phased income in this project as-is)
It has to compete with other plans to use PV to run H2 production and sell the gas to other markets displacing gas and oil. Possibly this could be a revenue stream while the cable is being built, but it begs a question of "why build the cable" -And its other capital funding this alternate build. It might "cruel" the market for this project
The cable has to go past several economies which would want a tap but who also extract ground-rent for subsea work. Indonesia is notoriously difficult about cable maintenance. So, there is potential for revenue to ID markets for electricity and at a significant discount of cable cost because it's so much closer: begs another question: why send the power to SG, when you can sell it to ID?