I just had an idea. What if there is a tool which algorithms create a brain wallet password from the fingerprint (or from multiple fingerprints of the hand)? Every fingerprint is unique. Therefore every password created by the algos will be unique, too.
Thus, one would never run into the risk of losing his or her password anymore. Perhaps there is something already. However, I do not know it.
Even if the wallet password is based on the fingerprint there should be always an alternative to unlock it like the phones.
Sometimes you can't put your fingerprint and you enter a password and unlock it(like the laptop,phone etc), which is still not 100% secure.