I received a tax return this year, which surprised me because I hadn’t filled anything out.
Turns out they just use the details provided by your employer, tax paid and send you your return.
I assume you can request a revaluation to submit additional expenses, etc.
Note: this is for standard employment. I’ve been contracting since then and have an app/service handling taxes for me now.
Disclaimer: I'm not American.
Larger sums of many are already tracked, so wealthy people would have already been monitored.
I don't know how you get under a $600 threshold, but exposing orders of magnitude more people to this policy is likely to do far more damage than to result in any good. This is already not just about wealthy people.
[0] https://www.overlawyered.com/2012/04/structuring-who-can-get...
[1] https://reason.com/2015/05/01/irs-steals-107000-from-conveni...
[1] https://www.irs.gov/e-file-providers/free-file-fillable-form...
Or be like rich entrepreneurs and run everything through a business (or foundation like Clintons).