From the article:
"There was a promising short lived moment where smaller, topic-oriented blog networks like Svbtle (amongst others) started appearing, but even those seem to have gone by the wayside and are increasingly being replaced by Medium."
Back in 2002 I co-founded a blogging company. At that time we were competing with the likes of Blogger.com and Typepad.com. There were many other companies, at that time, which I've since forgotten. At one point, around 2003 or 2004, we created a list of all our competitors, and there were at least 100 names on the list.
My point is, the vast bulk of all blogging has always been on 3rd party hosted blogging sites. Self-hosted blogging has always been rare. I self-host my blog, smashcompany.com, on a server at Rackspace, but this has always been a rare option.
All the same, I am intrigued by the question. If anyone has historical data on this, it would be fascinating to know when self-hosted blogs hit their peak. If Technorati.com has survived in its original form, then it would be in possession of this historical data, but sadly, the original Technorati.com is dead.