I'm inclined to think the Liberals 'threw' this election on purpose. The unforced mistakes: Their utter failure to capitalise on Labor's stumbles. Their failure to take a position and stick to it. The backflips on contentious issues. The failure to articulate a vision or inspire any motivation amongst their 'base'.
Why did we vote one of the worst governments since WWII back into power?
I suspect the Liberals figured they were in danger of inheriting the proverbial "poison Chalice" and they decided it would be better in the long run (for them), to let Labor keep hold of the ticking economic/social/demographic time-bomb their batshit-crazy socialist policies created and hope it goes off on their watch. Then, they could ride in like the Cavalry at the next election. Not that they have ever repealed any signifigant Labor initiave. They just make it sound 'nice'.
I don't agree that the problem lies in our preferential voting system. The problem lies in the average punter's ignorance of that system, coupled with the socially conditioned taboo on discussing politics, that indirectly prevents said punters from educating themselves to a level where they can vote strategically.
First-past-the-post systems are inherently unfair whenever there are more than two contestants. That's the conundrum the preferential system is designed to solve. The winning candidate can justly claim to have received more votes than all the other candidates, combined. An absolute majority.
I agree that the Liberals need to revamp their operation. They need to attract new members and lots of them. They need to become far less 'autocratic' and far more 'democratic' internally. And, they need an inspiring leader, not Mr Potato-head.
My biggest worry is that now the political Left, led by Labor, has won a "mandate", they'll do what all leftist/globalists do. They'll implement arrangements that will entrench themselves in power permanently. Things like the "hate-speech" laws are already being weaponized against critics of their "woke" globalist agenda. How soon before we have a "two-teir" judicial system like the U.K. where Whites are the second-class citizens? How soon before nationalist political parties that get too popular are declared domestic terrorist organizations and their leaders arrested and gaoled?
Maybe, the best immunization against Communism (globalist Socialism) is for a country to suffer under its yoke for a generation.