Currency instantly becomes meaningless, worthless. Economic system collapses.
Currency has no absolute value. It’s tied to economic production. If you take it all and arbitrarily redistribute it, that has a MASSIVE effect on the perception of it’s value because you’ve untethered it completely from the economic reality. So now that currency is just paper, it’s worthless.
Then… after the chaos and nightmare of the short-term, some new currency will be invented or take over, that is again tied to actual economic value in some way, and it then begins to distribute based on labor and trade, and not just divvied up arbitrarily. And we are back where we started, but just with the scars of that chaotic period.