Once you have BTC you can choose to store it outside of a bank as a non-inflationary asset. No one can remove it from your wallet.
Gold is less volatile, and the value of the volume of a €2 coin in gold is 9 months of El Salvador nominal GDP per capita.
Or the gold could be stored elsewhere and accessed via an app, with exactly the sort of database every bank already uses.
Either way, BTC adds nothing. Apps might, depending on the banking infrastructure, but BTC itself? Nada.
I guess the answer to the exchange problem is to have a decentralised exchange.