The decentralization means that we can remove the inefficient intermediaries (banks, lawyers, notaries, clerks, courts...) and replace them with computer hardware.
You're essentially saying that blockchains are more efficient because they let you dodge regulations? I'll grant you that, and it does make it harder to analyze.
But it's really tricky to disentangle these things, and I'd argue that it's not so much decentralization that enables these things as much as it is automation. A centralized entity could just run a blockchain themselves, right? Why don't they? Because other database structures are better if you have access to the advantages of centralization.
If you're saying that it's the blockchain itself that gives efficiency, then you need to come to grips with the fact that a blockchain is just a very inefficiently-designed database. That's all it is. It's designed inefficiently to allow for decentralization; its inefficiencies are necessary because when you decentralize you lose all kinds of robustness.
And admit it - your example of the house is a straw man. What does "list a house on a blockchain" even mean?
RE: World Economic Forum Says...You Might 'Question the Hype Around Blockchain'