I don't think they do address everything else - or rather, I believe that if you have to trust an entity for enforcement, you have a perfect avenue for everything else along with that. A blockchain is specifically designed for situations you have no trust in anything (except that 51% of mining power is not colluding in a specific way) - the rest of the time, there are much cheaper and simpler solutions.
The blockchain solves the problem of assignment and transference of property rights. Right now that process in many places is slow, expensive, error prone, and corruption prone. Blockchains completely eliminate that, full stop. Yes, you still need the authorities for enforcement, so obviously blockchains do not create some utopia where everything works perfectly, but they do solve big, real problems.
