This is one of the worst, and most misleading terms economic jargon. Because 'progressive' means 'improving' in every other discipline, people automatically equate progressive with 'fair', and don't actually analyse the situation further. Likewise 'regressive' means 'going backward' or 'getting worse', so people reject regressive taxes without further analysis. Many ignorant people even label a GST as 'regressive' simply because it is less 'progressive' than income tax.
Most countries have progressive income tax, but that does not mean that taxes are actually progressive - taxes depend on the choices that consumers make. A tax on speed boats would be a progressive tax, because the rich are more likely to consume them. However taxes on casino gambling, alcohol and cigarettes are generally regressive because poor people spend a higher proportion of their income on them.
Of course the majority of low-income-earners can't see this, and allow their governments to get away with it.
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