That doesn't mean that GPG is bad or that it isn't a strong tool, it means that for mass adoption then we need to make the tools easier to use.
Without help.
If he can do it, anyone can.
Someone here suggested that "PGP isn't too hard - you just need to spend 30 minutes studying cryptography before you use it" which pretty much makes my case for me!
In any case, it would be much simpler to direct someone to Proton mail, which uses OpenPGP.
I use Yubikey Smartcard both on my workstation and on my phone. The setup works, but its both exepnsive, takes a long time to set up and its fairly difficult to do. Now that I have the setup, I can only use it with a few friends.
Keybase is working on a more scalable solution. Every device has different keys and messages are encrypted for each device. This allows them to revoke individual devices. While deploying this to most non technical people, is still quite a challenge, at least its an attempt at solving the multi device problem. I can at least imagen how with their approch we could get wide use, while with traditional gpg I cant really see it.
How do you determine the keys associated with the people you wish to communicate with? (The web of trust and going to key-signing parties are about a thousand miles from 'everything just works'.)
I agree with you that if you want to actually improve the security of the people who are right now not using any encryption, make encryption easy to use. Even if this means that it might not fit the threat-model of those targeted by state-actors.
IMHO, PGP could actually be used for this (even if it might not be the perfect fit) by using Trust On First Use, better interfaces and more integration into mail clients. The problem is that it is right now a tool used and made by those who want really strong security. This includes e.g. encouraging you to set a passphrase, which makes it more secure, but also more of a hassle for most people.
[1] This is obviously only true if you don't fear it being compromised / your security requirements are low. But then, if you need strong security, use full disk encryption and Qubes or something similar.
Just because you can deal with complexity doesn't mean you should accept it, or seek it for that matter.