As treasurer in 2020, Perrottet wrote a tongue-in-cheek piece for the Herald in which he identified 10 Sydney structures he would like to demolish, including Blues Point Tower, the Cahill Expressway, the Aquarium and “anything brutalist”.

“I’m no architect. But I am an inhabitant of our stunning city, and like millions of other architecturally unenlightened residents, I care about what it looks like,” Perrottet wrote at the time.

“I like stirring the pot when it comes to Sydney’s architecture. We don’t give it the passionate debate it deserves.”

Road safety experts also questioned why the NSW government needed to use large gantries to display variations in speed limits given the increased use of vehicle GPS systems and apps such as Waze and Google Maps that provided verbal and visual warnings, and live traffic alerts.

Only this week, the state government announced updates to its own intelligent speed adviser app. John Wall from the Centre for Road Safety told Channel Nine that the app, called Speed Adviser, had been updated to alert drivers to mobile speed cameras and when they were travelling over the speed limit.

A 2014 review of this app and other similar systems by Wall, one of Australia’s leading specialists in the application of Intelligent Transport Systems for road safety, found Intelligent Speed Adaptation technology like Speed Adviser had the potential to reduce fatal and serious injury crashes by around 19 per cent.

President of the Australasian College of Road Safety Professor Ann Williamson said the government’s first response to managing speeds shouldn’t be to erect large gantries.

“Our freeways are over-engineered, they give the impression that you can drive 200km/h,” she said.

There were already large markings on the road displaying the speed limit, she said, but these were hard to see when covered in traffic (usually when vehicles were travelling less than the posted limit.)

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And while mobile phone and GPS intelligent speed systems were effective, Williamson said not everyone had a phone or a modern vehicle.

“If the role of the gantries was to let drivers know when they could drive faster on the Anzac Bridge, was it worth putting up a big gantry that is an eyesore?” she said. “You need something that shows clearly what the speed limit is, which is perhaps a little less obtrusive.”

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