And yet Australia is
the happiest country in Asia-Pacific.
Yes, the notional line speed into your home is only a constraint when nothing else upstream or downstream is a constraint. And even then the constraint may not matter. For example, how much do you care if it takes 2 minutes instead of 1 minute to download an update for your mobile phone or laptop — especially if it takes 30 minutes to install? Will it be worth paying extra to install an update in 31 minutes instead of 32 minutes?
M1 has very recently (only days ago) discontinued their 500 Mb/s plan for new subscribers.
Well, could the ISPs at least provide /56 IPv6 services? If you want to talk about lagging behind, start with that.
We can stop if you like. Nobody is offering anything below 1.0 Gb/s to new subscribers.
They could, but they didn't do that. Instead of $30.45 per month (500 Mb/s plan) they're charging $36.90 per month (1.0 Gb/s plan). "Be careful what you wish for."
M1 charges $39.90 per month ($3 per month more / $72 per 24 month contract) for 2.5 Gb/s. This is called price discrimination. It's like a tax on people who need more than 1.0 Gb/s (a small number of people) and who think "faster" Internet will solve their (other) problems (a larger number of people). And there's already a $6.45 per month tax now that 500 Mb/s is no longer available.
However, WhizComms is available at $21.80 per month (about $26.67 per month inclusive of initial fees and assuming one renewal at the same price since they're offering this price on a 12 month contract). That's for 2.5 Gb/s to the ONR thence 1000BASE-T ports. (You need to use multiple ports if you want to consume anything above about 1.0 Gb/s.)
No, anybody can go buy a wireless router with a 2.5 GbE WAN port on the open market. Whatever the ISP offers (and embeds in the cost of their service plan) may or may not be suitable equipment.