The reason that Taxes are complicated, is that the government wants them to be complicated. You can do without taxes (the government prints money, which is a tax on economic activity); or at a maximum print money + tax on big wealth accumulation which shouldn't affect the average guy.

The tax code is being used as a tool to funnel money through industries and as kickbacks to bureaucrats. A non-communist government can't force the population to do something (invest in this, build this, do that), but they can encourage/discourage it through taxes.

The tax code is not getting simpler any sooner.