This. I've been talking about this type of system for over a decade now too:
Adam Back
Adam Back20.8. klo 17.14
here's an argument i consider more persuasive for spam tradeoffs run amok: as bitcoin tech improves, we should have more cryptographic fungibility, and the blockchain converges to a cryptographic accumulator. you can't censor anything, you can't filter anything as it's all blobs.
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