As part of the carbon tax package, income tax was reduced, particularly for low income earners as a kind of compensation for the increase in cost of living caused by the carbon tax. The new government is raising those income taxes again, despite promising not to raise taxes.
If a goverment needs to have tax, It is better to tax things that you want to discourage. The carbon tax was discouraging the emission of greenhouse gasses, an unnecessary and dangerous activity, simultaneously providing necessary revenue. Income tax discourages the earning of income.