Good question. I looked in the attached essay source, and he covers this there https://dessalines.github.io/essays/why_not_signal.html#social-network-graphs

That's awesome! I'm always looking for tips and tricks, including stop making things too complicated with the tips and tricks (reaching for the 'ultimate'), and keeping it simple ;-)

Did you have any trouble convincing your friends and family to use PGP email encryption?

That is super cool! I've vaguely heard of Zettelkasten, but everything was in a digital context. To use it for pen and paper did not cross my mind till I saw this!