blockchain provides a publicly verifiable transaction history. of course enforcing exclusivity eventually boils down to giving some group a monopoly on violence, but the difference between using blockchain and a database in tracking who has the right to use that monopoly on violence to enforce their exclusivity is whether there's a verifiable public record of all transactions or just the current state of the data. It allows for the dispute of falsified records, and the automatic verification that all terms of the transfer between owners were met. It doesn't allow someone to sneak behind the scenes and do a quick "DELETE FROM home_owners WHERE owner_name='jrandomhacker'" and then go "Sorry, we don't have a record of your transaction 🤷🤷". You could make the logs of the database public, of course, but then the question just expands from "who has access to the database?" to "who has access to the database and logs?"