A case can probably be made that the original
Evangelion series, along with the cyberpunk anime of the 1990s, could be postmodern, in that they reflected one form of "dissonance" with modern society that contemporary audiences felt.
But I think it'll be as much a stretch to consider
Metal Gear Solid 2 postmodern as was my attempt with
The Rolling Girls.
Postmodern features — or "tropes", if you prefer — can be found, if you want to find it. But I think both titles were created with the main objective of entertaining people, rather than making a big statement, unlike say,
Akira or
Ghost in the Shell.
Anyway, here's the relevant quote from the article you originally linked:
In other words, with regard to Japanese pop culture, it has become difficult to differentiate the fad from the theory.
If you're really interested in the artistic movement known as postmodernism, you'd probably be better served looking elsewhere rather than otaku culture.