Medium of exchange or Strategic reserve for Bitcoin.

[X-ray]

If you're seeing from the perspective of bitcoin maxi, 1 bitcoin is 1 bitcoin and if we don't depend on fiat system too much, the volatility doesn't exist.

USD looks stable only because you don't pay attention to inflation. Overtime, unlike bitcoin where the volatility is bidirectional, it could go up or down. Dollar is rather 1 dimensional, it go down on the long term.

Bitcoin is a good medium of exchange and people need to pay less attention to the value in USD.

[Lida93]

Debates on this topic has shown that both price stability and consistent price rise can't be simultaneously achieved with such a volatile asset as bitcoin. So if we gonna have it as more of a means of exchange then we shouldn't be expecting a price rise anymore than we have, that means we will be experiencing a gradual price declining than an upside in value of bitcoin as it is with fiat. But serving as reserve where many buyers are accumulating in storage and not selling, pushing price more to the upside, diminishing any iota of  stability.
_{It's really confusing to put it straight out in words  for easy understanding}