Not at all. NZ is even less urbanised than Australia. The long-distance transit cables between cities in Australia all mostly already existed before the NBN even started.

You could cover more than 80% of our population just cabling up (literally) about half a dozen reasonably dense cities.

The actual reason is political. One side of politics privatised the state owned monopoly telco, creating a single huge, anti-competitive behemoth. That made progress with the internet stagnate for a decade. Then the other side got in, tried to work with the telco but they wouldn’t budge, and then surprised everybody by deciding to just build a provider-neutral network that was FTTP to 90-93% of the population. This was going fine - a few months behind schedule but on budget (projected at AU$44.1bn) after a few years.

But the opposition managed to convince a bunch of people in the media that it was hugely over-budget (despite the fact it wasn’t, and that all their financials were on the public record) and that a sensible solution was to stop that, and instead buy the old copper networks off the incumbent provider and spend a few billion to do a bit of an upgrade. They were “absolutely confident 25 megs is enough for anyone” and said this would cost max $29bn. They won Government, turned the network on its head and it’s just been one problem after another with huge widespread service quality issues, massive cost overruns, delays etc.

So now the cost of their “more sensible, cheaper, and quicker to build” network is nearing $60bn and finishing two years later than the original FTTP schedule (before they won Government, the party that wrecked the project promised to have it done by the end of 2016!)

So it’s just a big mess. Nobody really knows why they chose to do what they did when pretty much all the experts said to just continue with FTTP (they paid some consultants with links to their party to say their idea was great to get around that). Some say it was business links between party members and the incumbent telco, or the cable TV network they own half of. Others say it was because they had a deal with Murdoch (the leader of the opposition actually happened to have lunch with him the day before they announced their policy) because he owns the other half of the cable TV network. Perhaps it was just because they couldn’t accept that it was a good idea the way it was...

The "Australia is way larger" thing ignores that the situation in the cities is just as bad, or sometimes worse.

Australia is pretty densely settled though. I mean I have cousins on the Eyre Peninsula so I know what "thinly settled" means, but most people live in (comparatively) densely settled suburbs.

Then you'd expect the situation to get better in denser areas of Australia far more than it does.