Where do you get your "facts"? Your W-2 tells the IRS what each employer paid you in Salary, and what (if any) taxes were withheld. They also get statements from your bank, as your bank files, your 401K and Roth accounts as these people also file. If you were unemployed the State reports your Welfare earnings, and if you made significant earnings or filled contracts; those companies reported those expenses in your company's name. They know a HELL of a lot about you, the value of your home, cars and property. Welcome to "The Information Age".
You are wrong and do not understand how it works. The IRS receives from employers your wage info and it receives dividend and interest info from banking institutions but it (IRS) has no idea what your deductions are until you actually file a tax return.
I do taxes for my daughter and last year she had a combined income from wages, dividends, capital gains of just over $62,000 and yet she owed nothing and in fact qualified for a small refund.
In this case had she chosen NOT to file she would have NOT broken any laws.
Again. if there are NO taxes due you do not have to file a return.