Your linked post is not about faking PGP, it is about replacing PGP with his own implementation which supports only a subset of the PGP standard, the subset necessary to properly sign git commits.
I've not made myself very clear in the comment, but git and fossil scm are simply examples that delegate issues of trust to PGP's web of trust. Hardware keys are more secure, but from my understanding still stuffer from the same issue PGP does - a physical device is not an identity. keys.pub looks very interesting, but it seems that like keybase it doesn't address everyone's concerns[0].
From a technical perspective if keys.pub exists there's no reason that the proof process could occur at a layer above git rather than within git in some form of "social proof sidechain"-like structure.
I'm definitely going to keep an eye on key.pub, once they've addressed some of their coming soon items they'll be a very nice contender to keybase.
An odd way to put it, but yes, the simplicity of the OpenPGP standard is one of its greatest strengths. Somehow the standard has resisted just a ton of stuff that would be pointless over the long term over a great many years.