The OP has made it clear that he supports the concept of Real Money Trade if managed by the Devs. That is not up for debate, he has shown the support of using Real money as a means for virtual profit.

This chart has however been repeatedly thumped as proof of how it works. I felt that this was missing important data to be able to legitimately tie it to the core point, that it halts real money trade activity.

Based on the article, the plex implementation was not even considered when they made the graph. What does this mean for the relevance of the graph?

And even if it was tied to the graph indirectly, Plex implementation in 2008 means a 75% drop counting 2007 is an irresponsible claim.