Without HTTPS someone could alter the content, spread false information, inject ads, malware, and other stuff, redirect to some other site, …
(This is a general remark, but it goes for a blog post like this as well.)
The site owners could do all of that even with HTTPS, and no-one would revoke their certs. Just saying.
And the best Windows malware is actually digitally signed.
It's still a weak argument since it's extremely rare in practice that's why I suggested blaming the ISP instead since ISP's are the ones that have historically tampered with http content.