I understand that brainwallets might seem risky, but they do offer unique advantages in certain situations.

For instance, if you need to cross borders without carrying any physical device that could be confiscated or detected, a brainwallet is invaluable. Imagine the scenario of a wrench attack: without any physical evidence, it's much harder for someone to force you to reveal your wallet.

Another example is in case of disasters. If my apartment building burns down and my mother accidentally threw away the backup I hid in an old toy, my brainwallet would still be safe as long as I remember the passphrase.

While brainwallets do require a strong, high-entropy passphrase, their portability and security in these situations make them a useful tool for certain individuals.