There is a central record for each separate local government(located at the regional judicial office), with copies being sent to up the chain.
But the thing is - over here whatever is in that local deed book is the current legal state of the property.
Licensed notary is obliged by law to check the current legal state of the property, verify identity of the ones making the change, and do the change itself - but due to sorry state of the books first part isn't always reliable.
I am also not proposing a solution for USA problems, but for my country.
People say a blockchain is decentralized, but maybe it's more accurate to say it's a centralized system without anyone being in control. Which might in fact not be preferred to an actual decentralized system.
I don't know if you are American or familiar with how real estate works here. It is decentralized in a way that most countries are not, and there is insurance that people buy against mistakes and problems with transferring property. In a way, you could argue that a single blockchain to track real property would be more centralized than the current system.
"the vast majority of U.S. states have opted for a system of document recording in which no governmental official makes any determination of who owns the title or whether the instruments transferring it are valid"
https://en.wikipedia.org/wiki/Title_insurance
"A recording system combined with title insurance decentralizes records, creating redundancy. For example, when many records were destroyed in San Francisco's 1906 earthquake, out-of-town title companies maintained records that allowed landowners to prove ownership of their property."