Early in a press conference this week, Treasurer Jim Chalmers looked down the barrels of the assembled TV cameras and made what amounted to a plaintive cry.

“This country should be capable of a more sophisticated conversation about our budget pressures,” he said.

“What I’m trying to do is to give you a sense of what we’re grappling with, the sorts of pressures on the budget, and the sorts of options available to Australia.”

Chalmers made the plea for sophistication at the same time he conceded he had stuffed up earlier that day during an interview on Channel Seven in which he failed to rule out extending capital gains tax to the family home.

You can count on one hand the number of times any treasurer has used the ministerial press conference room to admit a mistake. But the mistake was on the politics around taxation – not the policy that has engaged a veritable forest of vested interests.

Just over a week since Chalmers used a speech to warn the current superannuation tax arrangements were unsustainable, federal cabinet signed off on changes it expects will raise about $2 billion a year from 80,000 people with more than $3 million in their retirement nest eggs.

Chalmers and Prime Minister Anthony Albanese went out of their way to describe this as a “modest” change that will also extend to the defined benefits superannuation schemes enjoyed by bureaucrats and MPs such as Albanese and former prime minister John Howard.

To head off claims of a broken election promise, the new policy – a tax rate of 30 per cent rather than 15 per cent on earnings for balances over the $3 million mark – won’t start until the next election in 2025.

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By pushing the start date to July 1, 2025, Albanese created a political wedge for his opponents (who will have to fill a $2 billion-a-year revenue hole). But the speed at which he and Chalmers moved on super also created problems for the government.

The policy was announced the same day Chalmers released a revamped tax expenditures report, which tracks the forgone revenue from the various concessions within the tax system.

The exclusion of the family home from capital gains tax tops that list. Coupled with other concessions around CGT, it is worth almost $72 billion. The concessions around super are worth about $50 billion.

Chalmers’ stumble on morning television around capital gains was born of his decision to release the tax report, which has been produced every year since the late 1980s, on the same day as announcing the superannuation changes.

Since becoming treasurer, Chalmers has warned of the budget’s growing pressure points. Aged care, the NDIS, health, defence and interest costs all mean there is a growing tension between how much cash is flowing into Canberra’s coffers and what the community expects from the government.

The tax expenditures report gives you a clear map of possible revenue sources.

The extra $2 billion a year forecast to flow from the superannuation change will make barely a ripple in a sea of budget red ink. It suggests Chalmers, depending on the political fallout from super, has to go further.

Tax historian and former Treasury official Paul Tilley describes any debate around tax in this country at the moment as “feral”.

The 2010 Henry review, along with former treasurer Joe Hockey’s abandoned Re:Think tax discussion paper and the short-lived discussion about GST reform by former prime minister Malcolm Turnbull and his then-treasurer Scott Morrison, have all come and gone since the last substantive overhaul of the tax system in 2000.

Tilley says the country seems unable to have a proper debate about tax.

“The whole tax debate is appalling. We’ve had one modest tax idea thrown into the mix and there’s been a frenzy,” he said.

That frenzy has been driven, in part, by the very nature of super. Every Australian has a stake in it, and at the top end there are substantial financial interests seeking to protect those lucrative reserves.

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In 2016, Morrison as treasurer outlined super reforms worth more in dollar terms than Chalmers’ proposals. They caused tremendous trouble within the Coalition and contributed to Turnbull’s struggles at that year’s federal election.

Under Labor’s plan, the $3 million threshold for the higher tax rate will, like the thresholds in the personal income tax system, remain fixed.

This has precipitated accusations that hundreds of thousands of people – some time in the 2050s and 2060s – would be caught in Chalmers’ super net.

As Australian National University’s Ben Phillips, one of the nation’s best economic modellers of the tax and transfer system, noted, the argument over the lack of indexation was unusual.

“In 30 years, theoretically more than 40 per cent of tax filers will be on the top marginal rate. But that won’t happen. This debate is getting silly (er),” he said on social media.

The indexation debate ignores how the personal tax system operates. The Parliamentary Budget Office has warned that despite next year’s stage three tax cuts, all Australians face an increase in their average tax rates without further tax relief by 2030.

Since Malcolm Fraser abandoned indexing personal income tax thresholds in the early 1980s, no government has given up the political advantage that comes from being able to change tax rates.

Chalmers opened the year with his 6000-word essay on the future of capitalism. It went to the global debate about whether the world’s economic infrastructure is working for ordinary people.

But the debate about super, and the reaction to it, reinforced that ultimately a treasurer has to keep their minds focused on events overseas and at home.

Tilley notes that the last two successful major tax reforms were driven by public consultation. Howard and his treasurer Peter Costello took their GST plans to the 1998 election while former prime minister Bob Hawke and Paul Keating used their tax summit of 1985 to unleash a raft of changes pivotal to the tax system today (capital gains, fringe benefits, dividend imputation).

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“If we’re going to get anything done you need a full tax review with a broad agenda,” Tilley said.

Chalmers’ tax expenditure report contained, for the first time, estimates on the cost of work-related tax deductions, those made by landlords on rental properties and even the cost for people to get their tax returns done.

That’s the clearest sign that if Chalmers can manoeuvre the superannuation changes through parliament without losing more political paint, further reform could be on the agenda.

Cut through the noise of federal politics with news, views and expert analysis from Jacqueline Maley. Subscribers can sign up to our weekly Inside Politics newsletter here.