Melinda Tan said even with the benefit of hindsight, many police could not say what they would have done differently to prevent driver James Gargasoulas murdering her husband Matthew Si, 33, and five others during his 2017 rampage.

"In other words, our families had to be sacrificed," she said.

"If this is the best Victoria Police has to offer, then we are better off protecting ourselves."

Gargasoulas was being chased by multiple police units while driving a stolen Holden Commodore after he had stabbed his brother on January 20, 2017.

He drove into the CBD, mowing down and killing six pedestrians and injuring 27.

Ms Tan said some officers offered heartfelt apologies while others remained egoistic and failed to admit mistakes.

"Some officers were more focused on their careers and safety rather than protecting the public," she said.

"You should not carry the badge or wear the title if you're not willing to risk yourselves for the community."

Ms Tan was scathing of police reliance on efforts by Detective Murray Gentner - who the inquest heard Gargasoulas was obsessed with - to get him to surrender before the rampage via text message and phone calls.

She criticised the force and City of Melbourne for being unprepared for vehicle attacks.

Gargasoulas must be the "luckiest person on this planet" to win bail despite his risk, left free to roam after stabbing his brother, returning to the crime scene to abduct his girlfriend, then avoiding capture until after his attack, Ms Tan said.

Her young daughter had asked her, "Why did Papa have to die?"

"Apart from the actions of the offender, I will leave that question for Victoria Police to answer," she said.

The older brother of victim Yosuke Kanno, a 25-year-old Japanese student, had a statement read to the inquest on his behalf.

"I see Australia as a country where you are murdered just because you just happen to be walking on the streets, while the killer is guaranteed a warm bed and cooked meal, as well as medical care," Junpei Kanno wrote.

"The offender, his family and all of you will go on with your lives without caring the slightest bit about it and get to enjoy your time with your family, having barbecues and parties."

Mr Kanno said the failure to find Gargasoulas' then-girlfriend, who has been called to give evidence to the inquest, was further evidence of poor police management.

The youngest victim, three-month-old Zachary, died after Gargasoulas hit his pram.

His "beautiful baby rolls" and "squishy body" were remembered on Wednesday by his grieving mother Nawwar Hassan-Bryant.

"He was too perfect and pure to be here and we're glad he is now back in heaven - a place as perfect as he was," she said.

The other victims were 10-year-old Thalia Hakin, Jess Mudie, 22 and Bhavita Patel, 33.

Gargasoulas was jailed in February 2019 for at least 46 years.

Coroner Jacqui Hawkins adjourned until May for closing oral submissions.

Australian Associated Press