Bitcoin is not widely used for dally payments yet, so volatile prices makes it difficult to use as a stable currency
Bitcoin is not a stable coin.
To be fair the user didn't say a stable coin, but as a stable currency. Bitcoin is not stable enough to use it for some purposes, but that is to be expected when its value is massively appreciating. One day this may change.
Bitcoin is not created to compete with any centralized banks so I don’t see any reason why bitcoin needs to eliminate local banks. Banks have been serving the people in their best possible ways so I don’t think it need to be stopped just for bitcoin to steal the spotlight.
You are confusing central banks with local banks. Unless you mean something else with this centralized banks, but nobody refers to them as this because they are inherently centralized by their nature.