Big superannuation funds are using “untrue gripes” to “relentlessly lobby” the government to overhaul tough performance tests designed to protect consumers from products with poor returns or high fees, according to two architects of the regime.

Funds are also accused of using the tests as “a convenient scapegoat” to justify subpar returns instead of explaining why their investments had fallen short, even as doing so risked losing customers hundreds of thousands of dollars by retirement.