NSW has been suffering for the last decade from a totally clueless government, and an opposition totally owned by its fringe right-wing. Labor couldn't govern their way out of a paper bag and the Libs figure that instead of drifting to the centre to meet the voters, all they need to do is wait until the voters give up and move to them.
NSW doesn't have any money, so they can't do any major roads project without farming it out to private investors and putting up a toll booth to pay for it.
This has led to some really bad policy decisions. For one thing, most of the new roads are bypasses that allow drivers to skip congested areas like the middle of the city. The toll then discourages people from using the bypass and the city remains clogged. Then to bail out the investors, the government closes lanes on the free alternative routes to force people to take the tollway.
There was an amusing couple of years where you could get away with not paying tolls just by driving through the electronic gate and ignoring the infraction warnings. Because the RTA was doing all the work of collecting the money but not getting to keep any of it, they didn't care enough to follow up people who didn't pay.
I have no idea how accurate those times are, I always assumed they would just be basic approximations but you may well be right that they could be more in depth.
When I lived there up to a couple of years ago, they were surprisingly accurate, even during fairly heavy traffic.
I can't recall the exact details, but from memory they use road counters at entries and exits to measure traffic numbers within sectors and, based on theoretical maximum number of cars per sector, predict whether traffic is capable of flowing at the speed limit or at some calculated reduced speed for each sector. The speed calculations, along with each sectors' distance, give you predicted trip time to the various exits on the display.
As I said, don't quote me, but that was my understanding.