If true, this is despicable. I can barely fathom what kind of messed-up corporate culture and labyrinthine decision-making process would lead a company to charge authors for making their articles 'open access' only to turn around and put those exact same articles behind a pay-wall.
Tales like this are exactly what has inspired us at Scholastica (https://scholasticahq.com/) to make it easy for academic journals to publish Open Access. I'm a member of the team and would encourage anyone interested in OA publishing to take gander at what we're doing. You can find an example of what an OA journal looks like on Scholastica here: https://scholasticahq.com/the-scholastica-example-journal
When I first clicked the link: (a) no open-access logo, (b) button offering me the article for $35.95.
I did not at the time know what the open-access logo was supposed to look like, so I went back to the article, found it, and clicked the link again: (a) open-access logo, (b) article in its glory.
My guess is that in response to this article someone fixed something and the article is now properly open access.
This seems rather sensationalist. Where, exactly, am I supposed to find these open access articles that Elsevier is charging people to read? Besides that unsubstantiated claim, the rest of the blog post seems to be nitpicking about how Elsevier makes shitty websites that are confusing.
Unless I misunderstood the blog post, when the author contacted Elsevier, the company's Director of Universal Access wrote back on an email that 'open access' articles can be distinguished by (quoting from the email) "an open access symbol and link in the top right of the article. For an example see here (http://www.sciencedirect.com/science/article/pii/S0168900207...)."
As I write this, that article costs $35.95 -- that's pretty convincing evidence, no?
Edit: as some comments below posit, it's also possible that the Elsevier executive provided the wrong link.
I don't see any evidence the linked article is actually Open Access.
It seems possible that the response just had the wrong link, and they article they are charging for isn't open access. http://www.sciencedirect.com/science/article/pii/S0168900210... is clearly Open Access, has a clear mark of that, and has full text available for free.
Elsevier is a monopoly in this space. Monopolies do this kind of thing because they can, which is why they should be broken up or legislated to enforce fair behaviour.
Edit: Yes, it appears to be true.