There will be a day in which people will stop caring about what a central bank man says or does not say.
I'm not so sure it'll ever happen like that. In the medium term, defending fiat will require extreme measures due to the expected increases in Bitcoin's purchasing power. And so the vast majority of today's fiat currencies will disappear
But in the long term, when Bitcoin reaches its limit (100x its current purchasing power, for example) then people will be more willing to hold other assets as long as those assets don't lose value too quickly.
If governments continue to demand taxes to be paid in something that is issued by their central bank, then that currency will continue to have some value, and central bankers will still (like today, if they choose) keep the value stable.
So I think it's likely that a small number of fiat currencies survive, and their banker's decisions will matter
But in the long term, when Bitcoin reaches its limit (100x its current purchasing power, for example) then people will be more willing to hold other assets as long as those assets don't lose value too quickly.
If governments continue to demand taxes to be paid in something that is issued by their central bank, then that currency will continue to have some value, and central bankers will still (like today, if they choose) keep the value stable.
So I think it's likely that a small number of fiat currencies survive, and their banker's decisions will matter
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