N.B. I'm aware that the author's goal was very different from mine. The criticisms I will mention are more addressed to myself than to his work.
This history is an interesting one as it starts with the invention of SMTP in 1981, 10 years before PGP invention, and situates its invention with a 1991 senate Bill 266 to ease electronic surveillance. Major historical events (the release of differente versions of the program, the publication of atlernative competitor (such as S/MIME or OTR), as well as vulnerabilities (e.g. Efail) are mentioned. There are also many criticisms that are mentioned and dated back in time.
However, several elements are missing in my opinion:
The author of this article did a pretty good job of centralizing many different elements of the history of end-to-end encrypted communication system. He situates the history of PGP among a broader history of communication systems over the Internet. However, it is a biaised history, as he does not present new developments and implementations of the program (such as the Sequoia projet, the Pretty Easy Privacy project, or many email providers that have native PGP support (ProtonMail, Mailfence, etc.). The criticisms he formulates about PGP are somehow very classical: he quotes, among others, the 2004 OTR article, Green's 2013 "What's the matter with pgp?", Valsorda's 2016 "I'm giving up on PGP", and Lactora's 2019 "PGP Problem", which present well-developed criticisms about PGP. Here's are the most important ones that the article mentions:
About this last point, it is interesting to note that when Efail was disclosed, in May 2018, many people, among others journalists, complained that this disclosure was putting them at risk and many voices from the infosec community criticized the disclosure process because of this. There is thus an obvious contradiction that would be interesting to dig into.
In general, the defenders' opinions do not appear in this article.
The author of this history also ignores the fact that much work is being done on the standard specification (see the openpgp-wg/rfc4880bis repository on gitlab) and many emerging projects have come into light (Sequioa, keys.openpgp.org, Pretty Easy Privacy, and so on).