I get it, certificates are hard, but having free certificates by Letsencrypt has probably been one of the most beneficial things that happened to the Internet in the last 10 years. If someone doesn't like it, please put in the work to come up with a better solution, not arguing for an even worse solution.
The author of this article doesn't propose anything workable. Mentioning SSH is ridiculous, it's not meant to access servers you don't know. Also, I have seen more than a few sysadmins who would easily be tripped up by a MITM because they'd just wipe their know hosts file at the first sign of trouble. And these are TRAINED people.