It was in fact about him critiquing the Harry Potter book series, though it seems he feels roughly the same about any work of fantasy.
Mr. Bloom is somewhat controversial. He still is held in high regard by parts of the cultural establishment and seems to have appointed himself to the task of Gate-keeper of the Canon of Western Literature.
Several others consider him a patronising gasbag or worse (e.g. Naomi Wolf). Anyone of such stature will have their detractors (justly or not) and it's easy enough to dismiss opinions of controversial figures like him. But wanted to figure out what it is in fantasy that irks him so much, because I'm fairly sure that that's the same thing that keeps people from taking their own imagination seriously. Or, in other words, what keeps them bound to the 'flatlands' (prisoners of he Archons).
(Limiting myself to Tolkien for now, I suppose that pretty much the same arguments apply to other fantasy)
I still have to find some actual writings by Mr. Bloom where he talks about Tolkien's work, until now I could only find some allusions and references. From there rises the image that the first thing that Mr. Bloom seems to dislike there is that he finds Tolkien's writing simply bad. He thinks it's archaic, supposedly considering it to be a deplorable and cheap stylistic trick.
But the reference that I read suggests that he main reason that Mr. Bloom dislikes Tolkien is that Tolkien doesn't play by the literary rules. For one thing, he's never ironic.
Never ironic.
That's interesting.
In the past few years I've been thinking whether it might be the ubiquitous irony that puts me off in so many (pop)cultural expressions. And ubiquitous it is, in any case for anything that's not too low-brow or naive.
So what exactly is irony? Fowler's A Dictionary of Modern English Usage says (in slight editing):
Irony is a form of utterance that postulates a double audience, consisting of one party that, hearing, will not understand the point; and another party that, when more is meant than meets the ear, is aware both of that more and of the outsiders' incomprehension.
Yeah, here we go again.
The in-crowd, exchanging smirks and meaningful glances while they enunciate ironic tidbits meant to communicate their togetherness and intellectual superiority

Of course there's more to irony than that. I know that. Irony has been employed by philosophers as far back as Plato. It's also been critiqued by many, such as Kierkegaard, mainly for its inability to achieve anything positive: irony may be a useful tool for criticism, but you cannot do much else with it.
What I mean is irony as it has become an all-pervasive and (I think) rather disruptive phenomenon. Since the 1980's at least, the mandatory ironic position has made it all but impossible to be earnest about anything, at least if you don't want to be sniggered to death by the cultural avant-garde.
I'm of course not the first to note that. the problematic role of irony has been thoroughly criticised by David Foster Wallace and others.
Still, I think that this has been an exclusively academic debate. I wasn't aware of it before I actively searched for it, and irony is still the defining characteristic of all highbrow culture - actually, even most contemporary low-brow pop culture and advertising is dripping with irony.
I think this is a problem. The ironic imperative prevents formulating anything positively constructive because irony only allows criticism and no creativity.
What do you all think?
Sources: The Problem of Total Irony in the Writing of David Foster Wallace, thesis by Frederik Gerding, Rijksuniversiteit Groningen