"[a medium post has been] doing the rounds the last few days, describing how an automated license plate recognition (ALPR) system being developed for the Australian Victoria Police could just use the open-source ALPR system OpenALPR instead"
The original post was pretty much a tech demo, and noted a bunch of issues. I think the point was that an ALPR project shouldn't really cost $86M.
ALPR is a well studied problem, there are a number of commercial solutions. I've no doubt there are even a number of solutions already deployed in Australia. Such systems are routinely used, for example, to monitor the speed of traffic (see Traffic master).
And as the original post showed, there are even open source solutions to the problem that work pretty well.
So yea... $86M seems like a lot when there are probably off the shelf systems you can buy at a much lower cost...