(Most of) Australia's problem is that the government stuck its head in the sand for a decade and pretended that renewables weren't happening. Consequently minimal groundwork was done by preparing the grid with suitable transmission and storage. Now it's being overtaken by the inevitable: renewables displacing coal/gas because they are cheaper to build and run. There will be a period of pain whilst the missing groundwork is done but it will get there.

I say "most of" as South Australia is showing how it can be done, with over 70% of its energy coming from renewables whilst not being blessed with hydro [1].

[1] https://reneweconomy.com.au/south-australia-grid-with-the-mo...