This article deals with Canada, which is a similar “swamp” to Australia, so it should be relevant:
https://business.financialpost.com/opinion/setting-the-record-straight-on-the-benefits-and-heavy-costs-of-immigration-to-canada
“In a recent campaign speech, Maxime Bernier, leader of the People’s Party of Canada, cited the results of one of our studies, which showed that recent immigrants are imposing a heavy fiscal burden on Canadians. He used this information to justify his plan to reduce future levels of immigration. The CBC had journalist Jonathon Gatehouse do a “fact check” of Bernier’s claim about the fiscal burden. In a publication sponsored by the CBC, he concludes that this claim is “false.” Since this verdict implies that our study also reached false conclusions, we feel compelled to do our own fact check of the analysis produced by Gatehouse. The author makes much of the well-known fact that immigrants have a positive effect on aggregate national income (GDP), which says nothing about the fiscal burden. He also fails to note that recent immigrants have lowered Canada’s per capita income since, according to official statistics, they have lower average incomes than other Canadians. He also cites a number of published studies and data he considers relevant. They involve well-known facts and again tell us nothing about the fiscal burden. For example, he notes that the gap in the unemployment rate between recent immigrants and native-born Canadian males has narrowed, but neglects to mention that this always happens when an economic boom creates increased demand for labour and leads to the hiring of previously unemployable workers.