With less than three months to go until the federal budget, you are going to be hearing a lot more about tax. It seems that something is finally going to be done to fix the capital gains tax, but already conservatives are working to give the richest another tax cut.

This week a Senate committee into the 50% CGT discount has held inquiries. My colleague Matt Grudnoff and I made a submission to the committee and Matt provided evidence on Tuesday. Regular readers, however, will not be in any doubt of my position. I have written long and loudly on the topic.

Not only has the 50% CGT discount distorted the housing market and coincided with the biggest decline in housing affordability in our history, but it massively favours the richest.

Those earning more than $250,000 a year make up just 2.5% of all individuals, but they account for two-thirds of all the capital gains:

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Little surprise then that the Parliamentary Budget Office has found that 59% of the benefit of the CGT discount goes to the richest 1% (or those earning more than $362,900):

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While the general tone of the evidence before the committee has been in favour of removing or at least reducing the discount, one worrying tax policy line has begun to be pushed in response.

The new shadow treasurer, Tim Wilson, has followed up his line that unemployment is too low by arguing high-income earners need a tax cut – because, poor dears, they are taxed too much to bother working.

Wilson told Sky News that he thought the 47% top tax rate was “punitive” and that it was “not incentivising work” – the argument being that those people currently on $190,000 just can’t be bothered working in order to earn anything over that amount.

While it was unsurprising that Wilson would argue high-income earners are the real battlers, it was more odd for the former ACTU secretary Bill Kelty this week to argue in his appearance before the CGT inquiry that the top tax rate should be dropped to 39%.

The problem for Wilson and Kelty, and those who argue that the very richest are being smashed by punitive taxes, is that the evidence totally contradicts this.

First, compared to elsewhere, Australia is not a high taxer of incomes.

Even among those earning 2.5 times the average wage – which puts you in the top tax bracket – Australians pay less tax than a majority of countries in the OECD and four of the G7 nations:

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But we can also compare the tax paid now with the past. The Australian Taxation Office has the tax rates going back to 1984-85, and the Australian Bureau of Statistics records the median earnings for workers.

This allows us to compare what someone on median earnings now (or those earning double or triple that amount) is paying in tax compared with what someone on median earnings did every year for the past 40 years.

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At most incomes, the current level of income tax is higher than it has been since the Howard tax cuts in 2006-07. But everyone is paying relatively less tax now than they were after the introduction of the GST in 2000.

Some may argue that because the average tax rate is higher than it was in 2007 that we need more tax cuts. But I am not sure why on earth we would view tax rates set by John Howard and Peter Costello as ones to emulate. After all, they were the ones who introduced the CGT discount and set fire to the housing market in the first place.

Moreover, the top tax rate of 45% (excluding the Medicare levy) now kicks in at $190,000, which is roughly 2.6 times median earnings. Are people earning that amount being smashed more than in the past? Is their “incentive” to work much less than it was for their predecessors who earned that much?

Nope.

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Someone on $190,437 – earning 2.57 times median earnings and just in the top tax bracket – currently pays $51,835 in tax, or 27.2%. Back in 2000-01, 2.57 times median income was $77,750. This was well above the top tax threshold of $60,000. But their average tax rate was 30.8% because other marginal taxes were higher.

Tax cuts to low-income earners flow through to high-income earners as well.

Indeed, if we look at who has benefited the most from tax cuts since the year before the introduction of the GST, it is pretty clear those on high incomes are not suffering:

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We are going to be told that if the CGT discount is removed or reduced then it is only fair that we give something to those most affected. This is bollocks. Undoing bad policy does not require rewarding those who have benefited from it. High-income earners are being taxed at roughly the same rate they have been for 20 years, and less than before then.

And they are not in need of even more tax cuts.

• Greg Jericho is a Guardian columnist and chief economist at the Australia Institute