I understand that when you say "unpredictable" and "not as stable," you mean bitcoin is highly volatile, especially when compared with national "stable" currencies that are being managed by the country's central banks. But the price of money is not the only metric to assess their stability. If you think about it, bitcoin is the most stable and most predictable currency humanity has ever witnessed. Bitcoin is a programmable money in which it is algorithmically determined how money should behave both in times of stability and economic prosperity and in times of depression and crisis. Bitcoin has a predictable monetary policy - far more predictable than gold or national currencies. Bitcoin issuance halves every 210000 blocks and you know precisely when miners will stop producing fresh bitcoins. You know that blocks are being produced every 10 minutes on average. You know on which principles these mechanisms are based because you can always inspect the source code. Bitcoin is the most predictable money out there.