Yes. This is more like diversifying your investments into different assets in order to minimize the risks. Let's say that you invest into Bitcoin, you can also choose to invest into different altcoins like Litecoin, Ethereum, Monero, etc in order to minimize the risks and end up loosing huge amount of money invested.

The ideal setup would be to have both a Bitcoin and bank account as you would have the convenience of fiat + Bitcoin (which provides decentralization, and serves as a deflationary currency making it even more scarce and valuable over time) Then, you could choose to sell Bitcoin towards your bank account, or even buy Bitcoin directly with it.