I think most people outside Australia (I'm Australian but have lived in the US for a long time now) wouldn't get this reference.
(Essentially, it's a politician who sockpuppeted his own social media posts to pat himself on the back, inevitably forgetting to change accounts and outting his efforts.)
Geoff Provest (Nationals MP) recently did the same thing commenting on an Albanese social media post pretending to be a disgruntled Labor voter