"These non-filer cases can be resolved by you in one of several ways: preparation of employment, excise, or partnership tax returns according to the provisions of IRC section 6020(b)..."
Why doesn't this say the revenue officer can resolve income tax non-filer cases by preparation of the income tax return Form 1040?
IRC section 6020(b) is the section authorizing the Secretary or his Delegate the power to legally "execute", meaning make and file, a return when a "taxpayer" who is required to make and file a return doesn't .
The authority to execute a Form 1040 is clearly missing.
If the revenue officer (who is fully authorized to act in the Secretary's stead in regard to executing returns) is restricted to the tax returns listed because of constitutional issues, then those same constitutional issues exist for the Secretary down through the chain of authority to the revenue officer.
As examined in prior chapters, Any tax on domestic compensation for labor would be a direct - unapportioned tax, and the 16th amendment does NOT allow a direct un-apportioned tax.