That deduction is no longer generally useful to take. The 2017 tax act basically made that not necessary for most people -- almost everyone just takes the standard deduction now.

The government already has all the info they need to create near perfect tax returns for everyone. The IRS doesn't necessarily have it, but the information exists in databases that can be accessed.

The way it's done in Japan, they send you a form. If it's right, you're good and you do nothing. If it's not, you send them a correction.