I currencly uses bitwarden to both save my password and totp codes, as this makes it easier to use on a computer when you can autofill both fields. However on mobile it is more cumbersome when you just need the totp code, you have to unlock the whole vault.
Perhaps this could be useful to reduce fruction for myself.
Another use is that currently saving totp in bitwarden is premium, while this tool is stand-alone and free to use.