First, forget worrying about the boats, the real problem has always been asylum seekers coming in by plane:
https://www.sbs.com.au/news/nearly-100-000-asylum-seekers-have-arrived-by-plane-to-australia-in-the-past-five-years
“More than 95,000 asylum seekers have arrived in Australia by plane over the past five years triggering fears over exploitation and slavery. New figures have revealed about 80 people per day since the start of July have claimed protection after landing at an Australian airport. But the Morrison government has defended its border protection policies, saying the number of arrivals actually dropped last year, compared to the previous one. The figures were disclosed in answers to Questions on Notice from Labor’s spokesperson for Home Affairs and Immigration Kristina Keneally. “There’s nothing wrong with claiming asylum. It’s an important right,” Senator Keneally said. “However, in 90 per cent of these particular cases, the individuals are not legitimate refugees and are often being trafficked to Australia for the explicit purpose of being exploited.” Labor is warning Australia is on track to post a new annual record for asylum seeker arrivals by air. It said 4,037 aeroplane arrivals have made a claim for protection between 1 July 2019 and 19 August 2019. But Immigration Minister David Coleman said that based on the same period last year, the figures were actually down for the number of arrivals seeking asylum. "We won’t be taking any advice from Labor, whose mismanagement of our border was an absolute disgrace," he said.”