The corporate watchdog says the shocking treatment of vulnerable customers by superannuation funds is a systemic failure of the $3.9 trillion sector, as the opposition slammed the Albanese government for repeatedly refusing to crack down on the misconduct of large funds.

Australian Securities and Investments Commission deputy chairwoman Sarah Court said there were widespread customer service failings on death and disability claims across the super industry. The regulator took the $94 billion construction industry fund Cbus to court on Tuesday over $20 million owed to bereaved members.