How does this compare to other popular solutions? Specifically, KeepassX / Keepass2 which are the most common solutions I've seen most Unix / Linux users employ. Can we objectively state which one is a better solution?
So it does, yes. I forgot about that, since I needed to write my own wrapper to paste both username and password (stored on separate lines) anyway. Thank you for the correction, I'll update my post.
There is also QtPass (GUI around pass), and various browser extensions (e.g. BrowserPass).
Of course one has to set it up, it's not an integrated solution. But GPG provides interesting features like storing encryption keys on hardware devices. Some devices like Yubikeys can have touch-to-use enabled. So each use of a secret requires a touch (after PIN but that's once a session). Perfect combination of convenience and security for me.
Pass encrypted passwords are kept in your computer, which I find safer than web based solutions. Optionally you can use git to share passwords between computers but you still need the gpg2 keys from the original repo.