Here’s a thought. In 1990 it went in the National Film Registry.
I know they refused to include the SE version of the original Star Wars. But what about Fantasia? Which version is in there? Sunflower or no Sunflower?
While I don’t know, my guess would be the same version that the VHS and Laserdisc got since it was put in the registry at the same time those were released.
So when you download this, you likely have a version of Fantasia that is better than what the Library of Congress has.