Bizarrely and lazily inaccurate
You took the time to write all those words and not bother looking up a few plans on the provider sites?
I am not doing your job for you beyond pointing out Telstra have been charging $10 for a 1GB data allowance as an add-on to a mobile plan for at least the last couple of years.
The following page shows a price for less coupled plans of $15 for 1GB
$10 for 1GB
$15 for 1GB