I think the biggest reason for hostility to Edwards' analysis is that he treats White Wolf and 2nd ed AD&D-style play - "storytelling" play - as a version of simulationism that misdescribes itself.
High concept simulationism is the "official" term for this sort of play, in which theme and plot are pregiven (generally by the GM or the module author), and the players then taking their PCs through that plot, contributing a bit of characterisation and other colour but not fundamentally shaping the story. It should be noted that Edwards is not per se hostile to this sort of play (and nor am I): as he says, Call of Cthulhu is the poster child for this sort of game, and (at least in my experience) a well-GMed CoC game is hard to beat.
Now for some players, there is already trouble at this point - because, for them, high concept play is seen as radically different from mechanics-heavy play of the RQ/RM variety - and so they balk at it being put in the same category as purist-for-system simulationism.
But that is an issue mostly just of terminology. Where the real trouble starts, I think, is with the "storytelling" idea - what Edwards' diagnoses as the self-misdescription of certain essentially high concept simulationist games. A misdescription, because in fact it is crucial to these games (as presented, at least) that the GM have control of the story, and that the players' contributions be colour only. (Of D&D modules, I would put a number of Planescape modules in this category - especially Dead Gods and Expedition to the Demonweb Pits - and also a number of 2nd ed Ravenloft modules.) These games therefore tend to produce illusionism (ie the GM controls things from behind the screen, while creating the illusion of player choice mattering to the story).
Now, for many players it seems that this sort of play is highly enjoyable. It is very common for illusionism of various sorts to be defended on these boards, for example, or even put forward as an inevitable feature of all RPGing. But, although Edwards' states that his essays are meant to be neutral as to playstyles, and although there is nothing in his definitions of high concept simulationism and illusionism that is inherently pejorative, it is obvious (I think) that he regards illusionist play as tending very strongly towards dysfunctionality (and Edwards elaborated his views on this in the notorious "brain damage" episode.)