At least Bitcoin isn't a fractional reserve currency. Bitcoin itself is mined much like Gold and has a limited quantity. The value of each Bitcoin is created and strengthened by the vast quantity of miners around the globe. Bitcoin is a store of value which moves in the direction of the media, government, businesses and developers who support it.
Bitcoin has limited quantity but not the stable value like gold so the chances of using it as reserve for value to any currency is null and bitcoin itself a currency whereas gold is not.
Gold price is not stable, it can in fact increase or less likely decrease from year to year, however it is by far more stable than bitcoin.
Bitcoin has a fixed quantity but not a limited one. If bitcoin adoption becomes global and demand >>>supply, the price will jump and the satoshi unit could be devised further to millisatoshi? nanosatoshi?...
That's an another story yet its just normal to think on about the law of supply and demand not only applied with Bitcoin which do have limited supply but on all sorts of things.
This had been an argumentation saying about Bitcoin is a value reserve which it really isn't if we do think deep through.