I think it's a joke. Though, the truth is, having AI write security sensitive code may actually genuinely be "AGI hard". AI breakthroughs are impressive, but I don't think we really know how to prevent the "confident bullshit" problem yet, and it's not clear it will be solved in this current cycle of progress. In many cases this might be an OK problem to deal with manually, but for security code it's probably not worth trying to. So the author might not have a threat to their job security, anyway.