If we had an honest-money system (that is, a 100 percent precious metal coin system), debates over tax rates would mean something.
In fact, under such a system, taxation would at least have a natural top limit; at some point, taxpayers would simply refuse to pay.
This is why tyrants, since at least as long ago as the Roman Empire, have relied on the much more clever system of indirect taxation through inflation.
In Roman days, the methods were rather crude. The emperor began "clipping" the edges off gold and silver coins, melting the clippings to create new coins. But this approach had its limitations.
Next, the emperor would mint "silver" coins that had much lower silver content. Then, he would start issuing coins....