I think he is referring to PGP being released.

1991 – Phil Zimmermann releases the public key encryption program PGP along with its source code, which quickly appears on the Internet.

Nice! Hopefully their experience can be used to help other agencies to move to Linux and open-source software. It also shows how long time it takes to move for a big organisation, in 2018 it was 82% of the PC workstations that was running GendBuntu.