Or even a signed hash against a confirmed/known/distributed public key.
Blockchain is only useful in a decentralized + adversarial context where there is a need to remove one-another's ability to game a given system. And even then, it doesn't imply a perfect security around it. Since it won't stop theft, breach, scams or other vectors.
How is this published? On a single server somewhere? What country would you put it in? A friendly one I hope. Also one that won't block access to other countries that it might have petty disagreements with in the future. It might be a good idea for it to be replicated across a number of servers across the internet. We call those "nodes" in the blockchain space.
So you're suggesting that publishing a hash in a newspaper every day is a better solution than a digital ledger? This is peak buttcoiner logic. That actually used to be done [1], because Blockchain are valuable, but not anymore because digital versions are more scalable, efficient, reliable, global, trustless etc. Etc.
Actually I would say that that is exactly what blockchain does, except as a protocol and relying on a network rather than a newspaper. Actually I might use this to explain blockchain to people on a base level.
Write once media on a server is what you want.