Yeah. Back from reading it. The conclusion you quote is completely based upon RAM demands. The RAM per node assumptions hinge completely upon a survey of machines running Steam. Other than to reiterate how absurd this appears to me, I shall refrain from further comment.

Well, after adding this... I can see the motivation for using Steam figures. They are publicly available, and form a fairly broad sampling. As such, they are an easy thing to cling to. However, they are a sampling only of a completely unrelated user base. Pity I've not been able to locate absolute numbers in Steam's data set. Any guesses as to whether or not the raw number behind the 15.8% of their Win user base that has 12 GiB or more completely dwarfs the 5555 or so full Bitcoin nodes?