It's a good point. Everyone living in Australia knows what "NSW" means, and it's a website that's almost always only used by people living in the state. Except for a page on dark patterns :)
Same blindspot as Americans using two-letter codes for their states (AZ etc.), or any other country's inhabitants using locally-known place names, or not adding their country after it.
Googling '"new south wales" site:www.nsw.gov.au', some pages have it apparently written out in full, but clicking through to the e.g. "State Flag" page, they've updated the page to say "NSW"!
Same blindspot as Americans using two-letter codes for their states (AZ etc.), or any other country's inhabitants using locally-known place names, or not adding their country after it.