Nice vid. If you didn't know the early history of PGP, the OG user's guide served as a great introductory read to the core concepts of encryption / PKI.
I was at codecon, many years ago, in SF, at JWZ's bar. I forget if Philip Zimmermann was there, or if his story was told by someone else. Basically plenty of hassle from the USA government about exporting a munitions (strong encryption source code). Court case (if not several), hassle at the border, tax audit, delays flying, etc. etc. etc.
Someone else stepped up, mentioned their similar story, and having talked to their lawyer about the statue of limitations. They released the proprietary RSA M4 encryption source code. A bit of cloak and dagger. A anonymous physical letter to some 3rd party, saying "I think you have the capabilities, I'd like you to post this source code, if you accept post to sci.crypt looking for Joe Random". The code was released anonymously, with no repercussions.
https://en.wikipedia.org/wiki/Pretty_Good_Privacy#Early_hist...
https://ia601407.us.archive.org/9/items/pgpguide.-lst/PGPGUI... (35pp, .txt) https://web.archive.org/web/20201205180542/https://www.tech-... (same, .pdf)