If we're sharing obligatory links, then a detailed critique of "The PGP Problem" is:

https://articles.59.ca/doku.php?id=pgpfan:tpp

It's true, though, that much work is needed to bring PGP up to the levels expected of modern crypto tools. Hopefully some of that will happen as a result of the work happening in the IETF:

https://www.ietf.org/archive/id/draft-ietf-openpgp-crypto-re...

and due to technology built around it, such as:

https://delta.chat/en/

https://autocrypt.org/