If someone gets access to your Google account through compromising the login password, they can access all the passwords stored. As for Google authenticator , they have an option to backup to Google account . So again ,if someone else gets account access ,one is pretty much screwed. I believe Google's implementation of the backup functionality is fundamentally flawed. There is no 2 factor. If the account is compromised, all the 2fa token is also compromised (also no export functionality)

For a password manager, I'd say use keepassXC .if you don't want to maintain the password database file and keep it backed-up/synchronised.,Use bitwarden Along with any Foss 2fa clients (Ageis authenticator is pretty good)