Because the economics do not add up. Renewables are cheap to build, and cheap to run, and the electricity sells for the same price as that from any other powerhouse.
The old argument RE's (excluding hydro) are cheaper argument usually falls over when they are required to provide despatchable power, so lets not waste our time on this.
Your comment on price is also not true, as two CSP projects have now been cancelled because they didn't have price guarantees for their lenders. The same will apply to any longterm bass load generation source, I did say before, coal, CCGT, nuclear, CSP etc.https://www.aemo.com.au/Electricity/National-Electricity-Market-NEM/Data-dashboard#nem-dispatch-overview
Annual price tables clearly show the loss of northern and Hazellwood lead to 30-50% rise in wholesale power prices which 2-3 years later still haven't been curtailed despite more generation capacity being added. What happens when Liddel closes in 2-3 years? NSw is already in a power deficit, Vic is on the line. Yes when the sun is up and the wind blows, things maybe good.
Today, the stupidity continues with SA exporting Open Cycle Gas Turbine generated power into Vic, is this not a wake up the system is broken?
The current market encourages fast turnaround low capex high opex projects.
Now delete the remaining coal power stations in Vic and NSW and what would you have? Darkness because there isn't a solution to deal with the loss of this capacity. Surely this based on the learnings from Vic and SA should dictate, base load power generation needs protection, not extinction.