Bitcoin has proven itself to be trustworthy, in less than two decades of it's creation it has gained so much reputation that it is called digital gold which clearly means that it is widely accepted as a store of value. Many currencies have been affected by inflation, it is easy for a government to print more fiat thereby devaluing their currency but Bitcoin limited supply has given it trust and people can hold it for long term instead of traditional currencies in a bank. Bitcoin can react to negative news and dip but it will only be for a short term and it will recover and rally, that is why it is a valued asset.
Keeping a large amount of money in fiat is the biggest mistake anyone can make. Interests in bank fixed deposits or savings accounts might not cover the inflation rate. Bitcoin price might be unstable but hodling it is far profitable and safer than holding any other currency. Bitcoin is gradually establishing itself as a safe haven and a potent hedge against inflation.