How can Eurozone’s sovereigns’ debts, not denominated in their own national/printable fiat currency, be considered 100% safe?

Sir, Laurence Fletcher in Tail Risk of August 28, writes: “Yields on German Bunds and other major government bonds have been moving steadily lower, as prices rise. That has burnished their credentials… as a safe haven in uncertain times”

Sir, how can Eurozone’s sovereigns’ debts, which are not denominated in their own national/printable fiat currency, be considered safe? 

The reasons the interest rates on that debt is low is the direct result of regulatory statism.

Risk weighted bank capital requirements that much favor the access to bank credit of the sovereign over that of the citizens.

That the European Commission assigned a Sovereign Debt Privilege of a 0% risk weight to all Eurozone sovereigns, even when these de facto do not take on debt in a national printable currency.

That ECB’s, with its QEs, have bought up huge amounts of Eurozone sovereign debts.

What would the interest rates on eurozone sovereign debt be if banks had to hold as much capital against their debts, than what they need to hold against European entrepreneurs?

@PerKurowski