Tornado Alley (PROG)

[hap0206]

It appears you are confusing the word "complexity." with the worf "understandability" -- from your first link:

Perhaps the largest barrier to prefilled tax returns is the complexity of the U.S. tax code, which contains benefit programs for education, healthcare, housing, child care, energy, and more. Even an IRS-designed software platform cannot properly assess the deductions and credits taxpayers qualify for because it depends on specific situations for which third-party data does not exist
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I am sure that each of those Code sections are understandable.but knowing that they even exist is beyond the knowledge of many taxpayers due to the complexity of the tax code-- years ago someone ran for POTUS proposing that a tax return fit on a post card -- likely a repub