The message to be taken from here is rather “don’t bother”, if you need secure communication use something else, if you’re just using it so that Google can’t read your mail it might be ok but don’t expect this solution to be secure or anything. It’s security theater for the reasons listed, but the threat model for some people is a powerful adversary who can spend millions on software to find something against you in your communication and controls at least a significant portion of the infrastructure your data travels through. Think about whistleblowers in oppressive regimes, it’s absolutely crucial there that no information at all leaks. There’s just no way to safely rely on mail + PGP for secure communication there, and if you’re fine with your secrets leaking at one point or another, you didn’t really need that felt security in the first place. But then again, you’re just doing what the blog calls LARPing in the first place.