I’ll take your word for it regarding The Jungle Book, but I personally thought that film’s discrete surround remix fared much better than that for The Many Adventures of Winnie the Pooh. Compare how the music playing over the opening credits (and a few other scenes) sound(s) on the 1996 releases with how they sound on the 2002-onward releases…it’s even more night and day than the differences between the matrix surround and discrete surround versions of “I Wanna Be Like You”.
That mix is the best way to appreciate the film’s score, but even that is not without its own problems. The soundtrack has no matrix-encoded surround information to decode despite being advertised as a Dolby Stereo track, so it’s only a standard stereo mix— in fact, in some scenes you can hear a doubled layer of score delayed by milliseconds in the phantom centre that was clearly supposed to be coming from the back of the room when fed through the right receiver. Not sure what happened when Disney mastered the disc audio but it makes fixing other dialogue/music sync issues, that do occasionally crop up, a flipping headache to correct.
These kinds of problems are most evident, for example, in the sequence where Rabbit gets lost in the woods; it’s almost impossible to ignore the music echoing in the centre field a split second after you hear it from the left and right, and Rabbit’s call for help near the end of the sequence clips pretty badly. Another mixing faux pas that drives me crazy is when Tigger talks to the narrator near the end of the film. For some reason, the mixer layered the score that’s supposed to be playing underneath the dialogue with the instrumental to what sounds like the “Wonderful Thing About Tiggers” reprise, resulting in a frustrating cacophony of music that was clearly not originally intended.
Those are just the examples that come to mind as of this writing. Despite its minor problems, the mix is still the best the film has ever sounded, and a Godsend for anybody still waiting for Disney to drop the complete stereo score via their “Legacy Collection” line. But I’m kind of digressing; the whole point of this wall of text is to further what was earlier said about Disney’s inconsistent attention to the quality of presentation of their A/V. Back to Fantasia, its last release obviously focused more on the video presentation than that of the audio, and it’s been that way since the 1990 Fantasound reconstruction. Again, the write up I linked to earlier highlights the issues w/ the 2000 and 2010 DTS mix.