Actually, if you work in a corporate environment, encrypting an email is just a matter of clicking one button. PGP + Outlook is totally UNcomplicated.
The only thing (as an end user) you have to set up is to load other people's public keys on your keychain, but even that is automated if both companies use a public key server.
That doesn't mean we don't need a better way for the average person to encrypt email... I'd like to see client-side GPG incorporated in to webmail solutions like GMail and Office 360. The GPG code could be run in the Chrome native client or in a client-side plugin (like LastPass does with your passwords), and public keys can be hosted on standard key exchange servers. Doing that would make the process about as transparent as it gets.
For now... GPG is pretty simple to use once you understand what a keychain is and how to create and share encryption keys. (All of this is point & click.) While I never use GPG for transmitting messages, I do use it for attachments.
For 90% of the public, this is really never a concern, but for those who work in industries where privacy is an issue, knowing how to use these tools is essential.