I don't think you are investing when your money is stored in your bank account, rather it is losing its value as a result of inflation and poor economic situation.
The BTC network and the traditional banking industry are very different, BTC is decentralized, the bank is centralized. If you have your money in BTC, you control it because the network is censorship resistant and permissionless, but if it is in a bank, it is controlled by the bank and your money can be conficated. You must have some of your money in the bank anyway, for spending, so it is up to you to decide the portion to store in the BTC network and in the bank.