https://www.ecb.europa.eu/press/key/date/2020/html/ecb.sp201104~7908460f0d.en.html  2/5  04/11/2020  The two sides of the (stable)coin  Risks would seemingly be mitigated by allowing stablecoin issuers to deposit funds in accounts at the central bank. This would eliminate custody and investment risks for stablecoins and underpin their issuers’ commitment to redemption at par value into fiat currencies. But other fundamental problems would then emerge.
International markets and investors understood immediately that the possibility of a political split on the euro could no longer be ruled out and started to “price” it in when assessing government bonds which – one day in the future – might be denominated in a reborn national currency (either very devalued or revalued).