E.g. Greens got about 12.2% of vote.
12.2% of 150 is 18, not 1.
https://www.theguardian.com/news/ng-interactive/2025/jun/02/...
The system while better is biased towards parties who can get the majority of individual constituencies based on geographic location. It relies on localized monocultures to get democracy for smaller parties. But that doesn't happen.
Current US senate (100 seats):
Republicans: 53 seats (Majority Party)
Democrats: 45 seats (Minority Party)
Independents: 2 seats
Current AU senate (76): Australian Labor Party: 29
Coalition: 27
Australian Greens: 10
Pauline Hanson's One Nation: 4
Jacqui Lambie Network: 1
Australia's Voice: 1
United Australia Party: 1
Independents: 3
So Greens are slightly over represented in the AU Senate based on aggregate vote if 12.2% is correct.