Ryan fell ill after going for a swim on Friday and died two days later at Sydney’s Prince of Wales Hospital.
Long-time friend Geraldine Doogue was shocked to learn she was in intensive care on Saturday.
“I couldn’t believe it until I was properly briefed by her partner Rory Sutton,” she told the ABC on Sunday.
“Even if she had become conscious, the doctors predicted she would have had significant brain damage.
“We all knew that that was about the last thing that Susan would have wanted.”
Ryan served in the Hawke government and was responsible for landmark sex discrimination and affirmative action laws.
The Sydney-born women’s rights trailblazer was also the first female Labor government cabinet minister.
She was elected to one of two newly created ACT senate seats in 1975 and campaigned on the slogan: “A woman’s place is in the Senate.”
Ryan was elevated to the frontbench after Gough Whitlam-led Labor lost the 1977 election, and in 1979 the women’s affairs portfolio was added to her responsibilities.
She introduced a private member’s bill in 1981 to ban discriminatory acts based on gender or marital status.
When Bob Hawke took power in 1983, Ryan was installed to education minister and minister assisting the PM for the status of women.
Her bill passed later that year and she was an integral part of the creation of the Sex Discrimination Act 1984 and Affirmative Action Act 1986.
Though those pieces of legislation, Labor leader Anthony Albanese said she “changed Australia for the better”.
“Before then women could be sacked simply for falling pregnant,” he told reporters on Sunday.
“Women suffered enormous discrimination and the sex discrimination act changed Australia in a way that was very radical at the time.
“Many of the things today that we take for granted were issues which were championed by Susan Ryan, and one is indeed in which she was vilified for her championing of those issues.”
Labor ministry colleague Paul Keating said her “great achievement” was to set in motion lifting Year 12 retention rates from three in ten in 1983 to nine in ten by 1996.
“This revolutionised education in Australia, most particularly for girls,” the former prime minister said.
She stayed in parliament for 12 years before quitting in 1987 after being demoted.
Ryan worked in several academic and industry roles and was briefly chair of Australia’s republican movement after the failed 1999 referendum.
She was then called upon to advise the Rudd and Gillard governments, with Australia’s first female prime minister Julia Gillard ” on Sunday saying the nation had lost a “feminist hero and Labor giant”.
“Every Australian’s life has been improved by her leadership on gender equality,” she tweeted.
“She blazed the trail for Labor women, including me.”
NSW Labor leader Jodi McKay echoed those words: “Her legacy lives in every Labor woman who seeks to make a difference.”
Later in life, she returned to fighting for the powerless as Australia’s inaugural age discrimination commissioner and then disability discrimination commissioner.
Prime Minister Scott Morrison said the Labor icon would be remembered as someone who sought to make the nation bigger and more open to every citizen.
“She leaves a legacy that will endure,” he said in a statement.
She is survived by two children from her previous marriage to diplomat Richard Butler.
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