Many independent publications cannot keep up with the amount published by the ABC and the Guardian. After those two the rest of the major media landscape in Australia quickly becomes centrist/right-wing from Nine's offerings to Murdoch's.
The Fediverse attracts Left-Leaning contributors because the commercial microblogging platforms aren’t appealing to them.
The commercial microblogging platforms (by definition) appeal to those who are right-wing. Now that the two biggest microblogging platforms are owned by either venture capitalists or capitalist puppets.
To U.S. Americans, anything to the left of fascism is “Left Leaning”.
Twitter had the appearance of being Left Leaning to the ignorant masses mainly because it was funded by Venture Capital.
When it matured and had to provide ROI, it became much more Right-Wing overnight. The oppression of 3rd Party Apps was the beginning of the end (even though Twitter wouldn’t have been what it was without Twitteriffic).