All taxes are so simple as to be computational and therefore susceptible to automation
Anyone who says otherwise is corrupt
Anyone who says otherwise is corrupt
Even if it couldn't produce a perfect tax return for me, it would still be much easier if all I had to do was (for example), click a few buttons to upload a few tax-deductible donation receipts, enter in the amounts, read through the rest of the return, and click "Accept".
Even if 20% of taxpayers still had to do their own returns from scratch -- which almost certainly would not be the case; virtually no one would have to do them from scratch -- automating it for the 80% would still be incredibly valuable. Even with a manual check/amend/approve step. It would save taxpayers tons of time and billions of dollars of tax-prep fees.
It's not that it's impossible to automate, but do we really want virtually every transaction going to at least 1 state and the federal government. Do we really want every transaction to have both parties identified? I'd rather keep the option of financial privacy open and just do a few hours of paper work every year.
(At any rate, the sales tax deduction is much less useful now with the $10k SALT deduction cap, as well as the increase in the standard deduction. Even if you manage to deduct $10k in sales+property taxes -- deducting state income taxes is disallowed if you deduct state sales tax -- you still need another $2k of deductions to make pass the standard deduction threshold... and that's if you're not married. It's even less useful if you file jointly. Annoyingly, the SALT cap isn't doubled for joint filers. I really hope it expires without extension in 2025...)
This very likely does not make a difference on your total tax bill, especially now that other deductions are limited (like mortgage interest).
Also, even if sales tax paid did make a difference on your tax paid, there is a simple calculator that estimates your sales tax paid that you can use instead of summing sales tax over all transactions.
If you want to play around with different scenarios, I recommend you try the tool "Excel1040" [1]. It is free but consider a donation. Works great in LibreOffice Calc but pay attention to the loading instructions.
The caveat is that if you deduct sales tax, you are then not allowed to deduct state/local income tax. And of course it can be quite a bit more work to keep track of all the sales tax you pay in a year, vs. income tax.
Things like out-of-pocket medical expenses and business expenses would have to be done manually. But that's fine! Automating 80% of the work is still better than automating none of it. And it would be 100% for the people who don't itemize (which, as I understand it, is the vast majority).
It would be easy for the government to send you its automatic, non-itemized calculations and give you the option of itemizing.