It's not a terrible argument. To put it differently, the value to the end user is not a direct function of the degree of openness, but the utility of the degree of openness.
This algorithm change could come across as more editorial and less empirical. It's publicized as highly targeted ("slightly over 2% of queries"), responding to small tech discussion (Atwood, SO, HN, quality launch meeting), and seemingly rolled out in a short period of time. The media could easily boil this down to "a small number people felt sites they liked were under-ranked, so Google moved them up a week later."
I mention this because Google often talks publicly about being entirely algorithmic, and elements of this narrative feel human.
This feels like mostly a PR piece to me. And reports seem conflicting.
Google doesn't seem to say what they did beyond that they "developed an algorithmic solution which detects the merchant from the Times article along with hundreds of other merchants that, in our opinion, provide an extremely poor user experience."
Techcrunch claims Google "compiled a list of hundreds of merchants (including DecorMyEyes) that provided “bad user experience” and algorithmically forced them lower" (http://techcrunch.com/2010/12/01/googl/).