When BTC price has stabilized for like 5 years, maybe it can then be used as store of value or as currency. Before that it will mainly be used as cash cow and high risk investment.
For usage as store of value, it is not necessary that the prices should remain stable. On the other hand, an asset which can be used as a store of value should have a constant, or increasing purchasing power. A perfect example is that of gold. It's price has increased by almost 100 times during the last one hundred years. But it's purchasing power has remained more or less constant.