Quality of the flash itself. Nothing, see the Turd of the Week
Historicial significance: idk. For 20 years this flash was inaccessible, complaints about a white screen persisted until today, when it was posted on the Ruffle Testing / Flash Preservation Crew, when Tom Fulp finally replaced the file.
Turns out the author uploaded an .FLA file that was renamed.
In other words, the file, another_goo.fla, became another_goo.swf. which means it broke, and it stayed like that for two decades. But not before Tom briefly unpublished the movie without context.