There has been a lot of discussion about the rating system on these forums, which can be found via the search feature.
Here is a post from last year regarding some updates:
I personally don’t know all of the details, but I believe the rating system on OGS has received very significant and careful consideration.
I’m not sure if the article that you post is entirely relevant, since OGS is actually using the Glicko2 rating system rather than Elo. Could you please clarify what you specifically meant to point out?