I have recently read the blog post The PGP Problem which outlines various serious shortcomings of PGP.
I think that Delta Chat and Autocrypt fix some of them, like the bad user experience and complexity. Still, others remain, like leaking metadata, being default-plaintext and the missing forward secrecy.
In general, the post shines a worse light on PGP than I had thought. Now I wonder what the implications on Delta Chat are.
Should we even bother to encrypt messages at all as long as PGP is used?
Can better encryption technology be used with e-mail as the underlying structure? The article mentions e.g.:
It’s theoretically possible to achieve a facsimile of forward secrecy using the tools PGP provides.