I don't think that Gould hated Mozart, but:

[Max Kuenkel <agent8698@seatac.net>]

I don't think that Gould hated Mozart. But I think that Gould had a set
of musical priorities that would not fit into Mozart's shoes, hence Gould's
Mozart sounds forced and distorted, because Gould the rebel wanted to walk a
mile in Mozart's shoes to make this statement: " To all you who say that
Mozart's shoes MUST FIT ME: you're wrong, they don't fit, look here, see?
There are other shoes besides Mozart's (other sets of musical priorities)!"
 I don't know if Gould ever talked about his musical priorities, except for
when he said, approximately, that any music that meant a lot to him was
contrapuntal in nature.
 Amazingly, Gould never talked about rhythm (or did he?), yet rhythm was his
first musical priority and is the most instantaneously recognizable feature
of his playing, right there in the foreground at all times (I mean that he
subordinates all other aspects of his playing under an iron-willed sense of
rhythmic drive or at least rhythmic organization). Maybe he took that for
granted the way he took his pianistic skills for granted and never talked
about them, either.
His second priority was harmony, which for him includes contrapuntal
elaboration of harmony. This he talked about quite a bit.
His third or lowest, by far, priority was melody (as such): you never hear
him talking about that (or did he?). He did not worship melody as such,
which is why he didn't know what to do with Italian Opera. He loved rhythm
first and then harmony/contrapuntal elaboration of harmony. I doubt
that he acknowledged the existence of  "melody" as an independent musical
element. I think that he could not conceive of  "melody" except as an
extension or elaboration of some specific integration of rhythm and
harmony, like the Goldberg Variations, that heavyweight piece of music of
which it can be said that the main melody (Aria), as a melody, is not part
of the essence of the piece, but rather just another variation or
elaboration.
 Mozart puts melodies on the table and starts building with those and awards
them the  highest rank in the compositional hierarchy (I think?), whereas
for Gould, melodies are surface, not depth,  variations, not theme,
elaboration of substance rather than substance itself. I believe that for
Gould even a fugue theme, like the one from "The Art of", was not something
that can stand on its own, some kind of absolute melody, but rather, I
guess, he probably thought of that theme as a mere reason for the following
contrapuntal elaborations to exist, which would sort of reverse things and
turn the elaborations into the primary substance, and the theme from which
they are derived into a derivative of some sort (??).
I admit, by now I'm getting a little confused: maybe this is one of those
"chicken-and-egg" situations. Did melody exist first or harmony, in general?