There are heaps of laws that are still in effect but in general common sense overrules. This is one of them - where it is necessary only for cases where parents need some reminding to not be lazy deadbeats.
I wouldn't worry about it if your child is a bit younger then 12 and you are confident that they are reasonably safe. No one is going to fine you unless you are sending your prep kid out alone to walk along the main highway.
Things are different in small towns compared to brisbane where public transport and suburban school neighborhoods are relatively safe places to be.