EITC eligibility, for example, depends on the aggregate employment and spending patterns of your household. The IRS does not (and shouldn’t) track when you moved in with your boyfriend.
The home mortgage interest deduction depends on your primary residence; if you have more than one, that means tracking how much time you spend at each.
Although you're wrong about the mortgage interest deduction, that is reported by the bank per address, and you have the list your primary address with your state tax authority, which the IRS gets a copy of.
I think you’re seriously underestimating the amount of data the IRS would have to proactively collect. “We get your tax obligation right 80% of the time!” isn’t an acceptable SLA. Kids are born, houses (and electric cars!) are bought and sold, community college classes are enrolled in, …
Re: Primary residence: Uhh, OK, so I report to my state tax authority who reports to the Feds. I thought the point of this thread was that somebody else would do all this for me, but for the evils of Grover Norquist and Intuit?
There is a reason TurboTax is popular -- because it's a better interface for asking those questions.
But look at other countries. They don't ask you to fill out a form. They send you a bill and ask if they missed anything. For 80% of taxpayers, they would send the bill and the taxpayer would say, "yep, that's right". And your taxes would be done.
The rest could keep doing it the old way.
> Kids are born, houses (and electric cars!) are bought and sold, community college classes are enrolled in
All things they already know about! Because when you claim those things on your taxes, they cross check that to try and catch you in a lie.
When the IRS audits you, they don’t come with their own evidence beyond the basic income reporting that yes, they could pre-fill into forms. It’s up to you to produce documentation that justifies your filing.
Our tax code is complicated. It relies on voluntary (but potentially audited) reporting and compliance. If you want to argue for a simpler tax code, great, but at the end of the day, either the IRS needs to collect a lot more data or we’re stuck with self-reporting.
So for 80% of people, they would never have to fill out a tax form at all. They could just get the tax bill and have it auto-pay (or more likely auto-refund).
And for the next 10% of people, who only take a small set of deductions that you can take on top of the standard deduction, you don't need even a two page form, you just need a wizard that asks a few questions like TurboTax.
And then for the rest they can opt to fill out the regular forms if they don't agree with how the IRS calculated their bill. This is how it works in pretty much every other civilized country (and a lot of uncivilized ones too).