It’ll definitely will be the best alternative at least and not totally going to replace fiat. It was proven time and time again that it can bypass restrictions of the government, banks, etc.
If you look at the protests in Canada, centralized fundraising platforms are blocking them from raising funds. Instead, they turn in to Bitcoin and have raised a lot of money. The same thing goes to the Ukraine-Russia crisis where the government of Ukraine have received donations in BTC. Binance also donated $10 million to them.
That's the advantage because no one could control bitcoin, once it's in your wallet it's easy to transfer it to any address you like.
Unlike fiat, when you store it in the bank, the central bank or the bank itself with whom you opened an account could freeze it based on the order of the authority. Bitcoin and crypto are decentralized, no authority at all so no one could freeze our transactions.
A true game changer for us in the financial sector where we fully own it rather than storing it to a platform with a 3rd party control.
That's the real purpose of bitcoin, decentralization will eliminate 3rd party, the only 3rd party we have are the exchanges if we decide to convert our crypto to fiat.
There's no doubt that when it comes to that aspect, bitcoin has edge over fiat.
We can be our own bank as we have the full control of our funds.
However, many people still prefer to trust their funds to the banks because they want this institution to secure their assets and be responsible about it.
They have others taking the responsibility of securing their assets to safety. And a lot of people don't know yet how to manage crypto.
Also, other financial transactions like housing mortgage requires to have an account from the bank. Which is why in some cases, having bank account is necessary.
Moreover, the volatility factor is one major factor why people are hesitant especially those who are not really knowledgeable with crypto market.