At some point in time I guess it will become either one thing or the other. It cannot stay both at the same time. Can it? Is it a healthy usage method to have it as both?
Just think about the currency in Venezuela and you will understand that volatility has nothing to do with payment options.
Their currency is much more volatile than most of crypto coins and it's still being used
In no case I would call that volatility
It is correctly called depreciation up to a point where a money token (be it the Zimbabwean dollar or Venezuelan bolivar, or whatever) stops being money. Volatility means change in value, most definitely in both directions. This assumes there is some value but when a money token loses that value altogether, it has nothing to do with volatility. And for the majority of fiat money existing in today's world it is strictly a one-way ticket, i.e. these monies can only depreciate over time. As I'm inclined to think, we can't actually call such depreciation volatility