I hate that I am going to say this: a blockchain of key/ownership?

Blockchain doesn’t necessarily need to have “Proof-of-Work” which is what makes Bitcoin and other cryptos so environmentally unfriendly.

It would be a fine method for tracking ownership from a trusted centralized source. And I mean “trusted” in the sense of “they probably won’t just make some shit up because they’d get wrecked in court”, not in terms of actual trust lol.

But you say “decentralized”, for most blockchain projects that’s just a buzzword lol, it’s very hard to actually pull off. Especially without a financial incentive ie operators taking a cut of every sale made.