[lettergram]

The tax is not accurate historically, for higher income brackets. Prior to 2018(?) you could deduct the majority of your state income tax from the federal income tax (the "Trump tax cuts").

https://nypost.com/2021/10/05/court-upholds-trump-law-limiti...

Basically, prior to that implementation, you were really paying MAX(federal income tax, state income tax). After that implementation, you could only deduct a maximum of $10,000 in state income tax from federal tax. So it looks more like: ADD(federal income tax - $10,000, state income tax)

[mrunkel]

I don't believe you're calculating the pre law change correctly.

You could deduct your state tax from your income for federal tax purposes. So if you made 100k and paid 17k in state taxes, your federal AGI was 83k. Post change, it would have been 90k.

The Trump era change was really a fuck you to high earners in states with high taxes. Shockingly, a majority of those people tended to vote for the Democratic Party.

[thelamest]

Funnily enough, that SALT deduction was disliked by economists, as regressive, inefficient and mostly pointless. It was bashed by policy think tanks from all sides, e.g. Brookings, CRFB, Heritage, CBPP, and Center for American Progress.