The front-line spinner stunned the cricket world Sunday when he announced his immediate departure from international and first-class cricket mid-way through the series with the Ashes already lost.
Australia head into Thursday's fourth Test in Melbourne with an unassailable 3-0 series lead and chasing a 5-0 clean sweep in the remaining two Tests over Christmas and New Year.
Swann's dramatic decision was poorly received on social media for its timing and suggests the England team are far from settled, commentators said.
"Graeme Swann jumped before he was pushed, leaving the England side as the stress of facing a 5-0 whitewash and mounting criticism takes its toll," The Australian's Peter Lalor said.
"Swann copped a barrage of abuse from critics in England who called him a quitter and questioned his decision to abandon the team with two Tests remaining."
Celebrity commentator Piers Morgan labelled the spinner's exit a debacle.
"You accept a place representing England on an Ashes tour, you finish it. End. Can't believe what's going on out here," he wrote on Twitter.
Swann, 34, told a media conference to announce his retirement that he could see no reason to go on with the tour now that the Ashes were lost as he was going to retire at the end of the series anyway.
"Swann has, like many of his senior teammates, underperformed on the tour and was under enormous pressure," The Australian said.
"Batsman Jonathan Trott left after the first Test, citing a 'stress-related illness', but Alastair Cook, Matt Prior, Kevin Pietersen and coach Andy Flower have also had their futures questioned as former England Test greats urge selectors to give youth a chance."
Australia coach Darren Lehmann's plan to attack Swann's bowling was also credited as coming off spectacularly.
The off-spinner was a match-winner in the series England won 3-0 earlier this year, taking 26 wickets at 29, but he has only seven at 80 from the return series Down Under.
"He's a big player when you've only got four bowlers, now they've got five with (Ben) Stokes in their side, so you only have to take one or two of them out of the equation and make their quicks bowl more. That was certainly a plan from us," Lehmann said.
The Daily Telegraph's Richard Hinds said England's tour will be remembered for "the sensational implosion of a team that had, just five months ago, posed and selfied on the dais at The Oval after winning a third consecutive Ashes series".
"For England, cricket had suddenly been reduced from the source of huge enjoyment, incredible self-worth and rich rewards to joyless drudgery. All in the time it takes to narrowly avoid decapitation by a Mitchell Johnson bouncer," Hinds wrote.
Fairfax Media's Chloe Saltau said Australia's mission to take Swann "out of the equation" had now paid off in astonishing fashion.
"The 34-year-old's decision leaves the touring team in disarray as it tries to avoid a 5-0 series whitewash..." Saltau said.