If abandoning your own currency and adopting Euros was such a big deal, the UK would have done it decades ago (while it was still a part of the EU). This benefits the bigger economies, at the expense of the smaller economies. Any fiscal policy is dictated by the bigger countries, and with identical currencies, the only policy left for Bulgarians is to cut wages in public sector. This will impact local economy, and ri…
In fact, without the Euro/EMU, Ireland's currency would likely still be tied to Sterling, as it was until 1980. This would be, ah, _not great_, especially at the moment. Clearly, at least in this case, the euro benefited a small country (in particular Ireland was spared the various fiscal shocks that the UK suffered as a result of Brexit and Truss).