That the word challange is overly dramatic plus technically incorrect (adding a deduction that the government could not possibly know of is not a challenge). In actuality you just add any missing deductions, double check the numbers and then submit. His proposed system is just busy work.
The problem is that I am not a tax expert and but it rings a lot of alarm bells of expansion of government power.
We're effectively bandwagoning behind Netherland's system while ignoring the massive differences between levels of government, size of population and scale, and the overall law making process.
All for a stupendous reason = Ease of filing. Filing taxes on a bus while on vacation is such a outrageously insignificant 'feature'.
That said I did not downvote.