on some level, income taxes are kind of stupid, because you're not really taxing labour. labour doesn't generate wealth, directly. income taxes are in truth taxes on property, and are in reality paid for by the employers, not the workers. income taxes are taxes on the profit of the employers, not taxes on the labour by workers. income taxes are consequently a kind of hidden corporate tax. you could just cut wages and shift the tax burden to the employer and it wouldn't make any difference in terms of collecting taxes, but it would help in eliminating ignorant attitudes in the working class. when you put the income tax on a person's pay check, you trick uneducated workers into thinking the money is being taken out of their wages. this can have extremely negative social effects, as it can generate poor attitudes about government in the working class.

my understanding is that this was initially done to show the workers that the government does something for them. it's supposed to make the workers say "i'm buying government services with my taxes, so my taxes are justified". instead, it tends to harbour resentment in the working class, which misunderstands who is paying the tax and thinks it's getting ripped off. this has backfired and should be undone.

the only deduction on a pay check should really be for public pensions. income taxes should be shifted to employer taxes, instead. it's a trivial accounting shift that only happens on paper, as employers are the ones that truly pay income taxes, anyways. you'd do this by asking employers to pay a kind of head tax based on the number of workers they employ, and the number of hours those workers worked. if the employer pays out x number of hours of labour at n % income tax, it would pay x*n% in taxes. it would need to file that with cra at the end of the year, and workers would still need to send their stubs in to verify their hours worked, but the actual taxes would be done and paid for by the employer, not the employee. tax credits would work functionally the same way.

this would lead to stagnating or declining wages (not real wages, though.) for a while until it balanced out, but you would hope it would lead to more positive attitudes in the working class about the value and function of government services, in the long run.