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That's called an hash chain[1], they've been around for a while. In my country, receipts systems are actually required to implement hash chaining to allow the authorities to detect "missing" receipts (for tax-avoidance control purposes).

[1] https://en.wikipedia.org/wiki/Hash_chain

It's actually one of the few non-insane ideas about blockchains. But it has already been done as another commenter already posted.

check out certificate transparency https://www.certificate-transparency.org/

That's not quite the same, but I just found this NeoDNS[0] proposal, and it seems to be just what I described.

[0] https://rot256.io/post/neodns/

edited: Apparently it was briefly discussed at HN only 2 days ago: https://news.ycombinator.com/item?id=12370146