You can "volunteer" to pay taxes, or you can "volunteer" to have everything you own taken away, experience harassment and threats, and go to prison.
Sounds like a win-win.
Our system is “voluntary” in that, we all file tax returns, and declare, under penalty of perjury and other legal sanctions, that we are reporting our income to be taxed.
And then we voluntarily, on the honor system, write a check or wire money to the IRS, to pay the taxes on the amounts we voluntarily report to the IRS.
I think the point they were trying to make, is that none of us get a tax bill as such, to be paid on April 15th. We have to take the initiative to calculate what we owe, and then see that it gets paid.
The IRS will send you a bill, if you file the return but don’t pay the taxes. But their bill would be for the balance due that you or your tax preparer decided was owed.