Even so the root of trust is still the country and real estate reccord

If you trust a regular website you can even skip any cryptography a just use regular web site.

Signatures can eliminate the trust in the web service modulo middle man attacks on the identity associated with the keys used to produce the signature.

But unless everyone can physically check the whole history of the home building, the contracts, the reselling, fixes etc blockchain are not going to bring anything, you still need a trusted third party.