This is a really good (and entirely non-technical, for those who glaze over at equations) summary of a very thorny issue: repudiability in digital communications (it's technically only about DKIM, but the points made apply to other protocols than email).
I think I do agree with the conclusions, but it's something that isn't always so clear (how useful *in reality* are protocols like OTR, for example?)
https://blog.cryptographyengineering.com/2020/11/16/ok-google-please-publish-your-dkim-secret-keys/