Isn't an appearance thing moreso a cultural assimilation thing. In my experience, Arabs, Africans and East Asians that migrate here tend to make zero effort to take on the Australian mindset or way of life. They end up being perpetual foreigners who culturally clash with the mainstream unlike other migrant groups (as you pointed out, only 2% of the people who live here or so are truly native). My grandparents moved here from Spain in the 40's so it isn't like we have been here ages but you don't see Greek, Italian, Spanish etc. ethnic enclaves like you do with other demographics. There are suburbs in Melbourne, eg Dandenong that are so heavily populated with Afghani people it is like a slice of the Middle East transposed here. Similarly, Box Hill central looks like something out of Kowloon. Founded on sweeping generalisations yes, but some migrant communities (eg. The Sudanese, who end up feeling societal disenfranchisement on account of cultural incompatibility and form gangs like Apex) don't come here to assimilate, they come here to benefit from the collective while retaining a greater allegiance to the culture they know from home.