This presupposes that parties that be are static, that no new challengers are possible and that Labor is the "sole party of governance" (which is a pretty undemocratic notion). It also pretends that people will continue to vote Labor indefinitely just because the LNP doesn't exist.

The Greens, to some degree, purposefully position themselves as the party to "work with" the Labor party, and extract concessions from them. Which historically has been pretty meh if you ask me (they royally dicked around with the ETS and called that a victory, for example). They're also barely a left wing party: they talk about workers rights, yet don't push to undo the Accords (which means striking is illegal except for protected industrial action, thanks Labor!), they want dental into Medicare, but see no reason to campaign for abolishing our system and replacing it with actual universal healthcare (we have a private subsidy model, with a bit of public healthcare sprinkled in). Their party is one who want to manage capitalism better and tax companies and the wealthy some more - not abolish the power structures that allow the wealthy to retain the monopoly on decision making in society, and put agency in the hands of the workers (i.e. socialism). They think the solution to our problems is to get "good people" to the levers of power. They're quite fine with capitalism. That's not very left wing, if you ask me.

Moving politics left isn't about moving the Labor party left. The Labor party has and continues to move to the right. They are a lost cause and anyone who's still a member, despite it all, is on board with that.

The only semi-realistic threat right now is a far right cooker party in One Nation and Labor doesn't need to move left to combat them either.

Exactly my point. Having a "strong opposition" of a right wing party does nothing to move politics further left. And anchors the average opinion further right.

Do we really think the Labor party would have changed capital gains the way they did if right wing politics in Australia weren't in shambles (yeah, One Nation is rising, but they're so far much less effective in convincing wealthy people about much of anything).

In conclusion, yeah, can't wait for the LNP to die. Not that I think that'll be enough to usher in meaningful change. That will only come from grassroots organising.