Almost all countries have some sort of Federal Insurance for bank accounts. In Europe it’s 100.000€. In countries like Russia or Serbia, maybe it’s less than 20.000€ but there is always some amount that is insured (per account holder, sometimes per account. For personal bank accounts. Business ones usually excluded). Up to said amount, it is to be expected that even if the bank went under, the government would pay you back up the insured amount (law tends to say within days, it can take months).

This is why it’s smart to keep money spread accross banks (I mean, within reason, not 3k in each bank). And also to have money in different countries, which financial systems aren’t strictly codependent. Owning assets (stocks) or lending money to companies/countries (bonds) is another way to diversify.

Everything carries a risk. Cash is a liability of a State. Some will say “only gold is not a liability of anyone” - and they’d be right. But if the financial system globally were to collapse, good luck exchanging gold for goods and services. tl,dr: if you have enough money, use more than one bank, if possible more than one currency, if amounts justify: more than one country. Keep some cash. Good luck and don’t worry. Everything is going to be OK