The argument for Solar always sounds a lot like terra nullius, that was used to dispossess indigenous Australians of their land, and later their land rights.
Large scale solar is likely to cause problems for large numbers of native species. YMMV in how important you find that, but to me personally it is a huge issue.
Australia is a MASSIVE country, that is largely uninhabitable by humans. It is estimated that 75% of the species on the continent are undiscovered: https://www.abc.net.au/news/2014-09-07/75-per-cent-of-specie...
Large scale solar is likely to cause problems for large numbers of native species. YMMV in how important you find that, but to me personally it is a huge issue.