Isn't the other way around? The way I remembered it, having a blog was the hottest thing, and RSS is the solution that bring the blogs to the customer. Desktop clients are spawning everywhere (like Twitter clients a couple of years ago). It was a big when Firefox added support for RSS, and then my favorite email client back then, Thunderbird also had RSS reader built-in.
IMHO, it was the rise of _Web 2.0_ (oh boy, that term sounds so corny now) and uncontested Google domination of the web that made Google Reader the RSS client.
The article is right about one thing though, it's Flipboard and other "smart" reader apps killed Google Reader. Had there not been so much innovation on the reading side of things, Google could have (and probably would have) revitalised Reader like they did Gmail.