I agree, keeping a backup of the config file is a good approach.
But also, your password is being "obscured" before written to the config file, which means if you don't remember the original password you will not be able to re-create the remote from scratch without "sneaking" in the already obscured password from your backup config. So I would say that keeping a copy of the password (and also the "optional but recommended password or pass phrase for salt", which is effectively another password) in a safe place is also recommended. And then, if you can easily reproduce the rest of the remote configuration apart from your password, keeping the password is enough.