Modern streaming services often "remaster" shows, scrubbing away the film grain or cropping the aspect ratio. Sometimes, original music is replaced due to licensing rights. The uploads on the Internet Archive act as a "raw" backup. They ensure that future generations can see exactly what a kid in 1999 saw when they turned on their tube TV.
Relive the Classics: SpongeBob Season 1 on the Internet Archive spongebob season 1 internet archive
The Sacred Digital Vessel: How the Internet Archives SpongeBob SquarePants Season 1 as Cultural Monument and Technological Artifact Modern streaming services often "remaster" shows