Your example seems to be mostly coordinated through Rolex and authorized dealers, so what is the advantage of a blockchain? Why not just have Rolex keep track o

Your example seems to be mostly coordinated through Rolex and authorized dealers, so what is the advantage of a blockchain? Why not just have Rolex keep track of who owns a watch through e.g. a web interface tied to a serial number + username/password combination, that also allows transferring of the ownership of a watch to a different user? This would be much more user friendly, since you could have features such as "forgot my password" which are (by design) impossible to implement on top of a blockchain.