Both are not inherently bad but it is all about how they are used. If you are using fiat money to create debt capital to funnel into inflating the price of already existing assets you are misusing fiat money. If you use taxes to fund purposes which do not deliver net benefit to citizens again that taxation is bad.

However if you use fiat money to direct capital toward purposes which can reasonably be expected to deliver increased productivity and competitiveness to the economy then the debasement that fiat capital issuance causes can be (arguably) justified. Equally if taxation revenue is directed toward uses which increase productivity and competitiveness of your economy and ultimately its wealth creation capacity then taxation can be justified.

This entire debate is another example of Libertarians tragically misguided and simplistic misunderstanding of government and its crucial role in the wealth of nations.