> The news site which stopped updating in 2007, the blog somebody last posted to in 2011, that sort of thing.
Interesting, that hasn't been my experience. There's a certain group of stubborn techies who have active sites lacking HTTPS. One example is Dave Winer's blog:
He's doing some really interesting things over at https://feedland.com, so I'm glad I clicked through the TLS warning on his blog.
There is always someone who has a different experience, but I think Google numbers 95-99% is pretty much correct and websites with decent amount of traffic all have HTTPS.