Also nobody is talking about the advantages of (strong) brain wallets, that are actually making them more secure than PRNG based wallets.

Besides of the two I mentioned already:
- They don't rely on anyone's (publicly known) implementation of the "entropy"
- They don't require backups

There is more:
- They cannot be seized
- They don't need to be carried
- Their existence can be denied / can't be proven
- Even if someone can prove that a brain wallet had existed at some point in time, he's still unable to prove that you have not forgotten the password

These are mostly about legal security, but isn't Bitcoin's success itself exactly about it?
You see, in my opinion, the biggest enemy of the brain wallets should be the government.