Immutable, decentralized ledgers are useful for things (oh, hey CT logs, how do you do?).
Immutable decentralized ledgers are not useful for legal constructs like ownership, since in the current (and foreseeable) legal construct of property ownership is held by centralized records for which the state is the arbiter. This arbitration happens through either registries (for example, automobile, real estate, business ownership, etc), or through the courts. In order for blockchain technology to replace this legal construct in a meaningful way, there would need to a mechanism for a central authority to provide clear arbitration and resolution.
If the state can't meaningfully and authoritatively reassign those ownership rights through a legal process, then blockchain is simply a non-authoritative ledger, at which point it's existence is marginally useful since it is expensive, technically challenging to operate, and fraught with risk due to potential abuse cases from implementation errors.
This is one simple example, and doesn't dig into the fact that implementing laws as code is also problematic in countries where those laws can be rewritten by elected officials and courts.
Blockchain and bitcoin might become more useful in the future, but so far almost all blockchain uses that have gained traction have done so by grifters and the remora like folks who have attached to the bellies of the blockchain industry to enrich themselves while throwing around terms like legacy finance until their employers implode.