Do you think that Christians should obey the tax law, even if the rules required that taxpayers must donate 99% of their income in taxes?
This is a facetious hypothetical argument. The implication is that if the answer will object in the extreme, then it is justified to reject the point when it isn't extreme. See Hypothetically Speaking for more on this style of argumentation.
The simple fact is that Christians are to obey governmental authority. "Let every soul be subject to the governing authorities. For there is no authority except from God, and the authorities that exist are appointed by God. Therefore whoever resists the authority resists the ordinance of God, and those who resist will bring judgment on themselves" (Romans 13:1-2). Since governmental authority is derived from God, the implication is that obedience is owed, so long as the government is following God's laws.
The question poses an absurd situation because the simple fact is that no government can survive on such a tax rate because its citizens would not survive. The closest one could come is a communistic style of government where the government controls all commerce and fixed amounts are returned to the citizens. Such governments have shown themselves to be unstable over the years and do not survive long.