I've always looked at cryptocurrencies more as good alternatives to awful fiat currencies and unlikely to supplant good fiat currencies so long as those currencies are generally well-managed. You generally cite the Euro but don't forget that Bitcoin just lost like 70% of its value this summer (in addition to other cryptocurrencies losing much of their value as well), neither are immune to volatility. In this case in particular it's jaw-dropping to see just how supreme the USD is. Rising interest rates in the US to combat inflation are basically wrecking major currencies, including cryptocurrencies.
Personally I think long-term that the fiat monetary system will dissolve or be relegated to just a few countries (US for example assuming it doesn't collapse at the hands of the Republican party) and many countries (if they continue to even exist and depending on what amount of State is left over) will resort to bartering, a mix of USD and various cryptocurrencies, gold, and trading labor for commodities.
If (and you did) you had your choice at the start of the pandemic (pre or post crash, take your choice), between the dollar, BTC, euro, or the lira, which was the best choice?
Probably the one that's up 2x pre-crash and 4x just after, rather than the ones which are visibly eroding.
The dollar is of course the tentpole. Such a great basket to put all the eggs, innit.
Why limit your choices to only these specific assets from a "currency" class? Why not include other cryptocurrencies and fiat? And of what value is hindsight here anyway?
The other mistake that's typically made though and I could have expanded on this earlier in my post is in comparison of different "currencies" whereas each have different attributes. BTC for example as you note appears to be deflationary with respect to fiat currencies which are inflationary by design and policy. On the other hand I can't buy groceries with BTC so I would have died during the pandemic and Dollar and Euro would have been superior choices.
Personally I think long-term that the fiat monetary system will dissolve or be relegated to just a few countries (US for example assuming it doesn't collapse at the hands of the Republican party) and many countries (if they continue to even exist and depending on what amount of State is left over) will resort to bartering, a mix of USD and various cryptocurrencies, gold, and trading labor for commodities.