There is no stable term for the price of bitcoin and until whenever bitcoin will remain fluctuating, decentralization is the reason why bitcoin cannot be as stable as USD or other fiat currencies.
I know that people say that when Bitcoin will be adopted, it should become stable because there is a limited amount of it, but I don't see how it's gonna happen. From what I see people treat bitcoin as an asset to invest and hold and I can't imagine that will change in the future.
Now that adoption has taken place everywhere and bitcoin is also unstable, its finite number makes it difficult for bitcoin to stabilize and for this reason it is also possible that bitcoin will never be stable as the process of supply and demand will play its part. Bitcoin will remain an asset to invest in and I don't see it in the future becoming a stable asset.