The price of bitcoin will not be stable, but it may not be as volatile as it is now. Adoption should be the reason why bitcoin price volatility may decrease in the future, but it seems the government is more concerned with CBDCs than bitcoin adoption.
So far, bitcoin is more dominantly traded than used as a means of payment. If one day this condition can change then I'm pretty sure the price of bitcoin is much more stable than now, especially if the use case as a currency is more dominant.
Bitcoin is dominantly considered as a store of value, there might only be a small percentage where some people are trading their Btc, but mostly it is being held for a long term profit.
If Bitcoin will be used as a currency more than what it is today, volatility might be minimized. However, even If all Btc is mined in the future, If we keep doing what we do with Btc today, volatility will never end, but who knows what will happen in the next 50-60 years most of us might not be here anymore to witness the next BTC evolution (whether or not it continues to be volatile).