Yes... for many forms of digital transmission shorter is definitely better. S/PDIF, lightpipe, FW, USB, they all have maximum practical, recommended length standards.
There was an "audiophile" magic-cable vendor (perhaps you know the type of outfit, they promise you can just about count the molecules in the air because of the enhanced signal capabilities of their x hundred/thousand dollar cables) who was promoting a "longer is better" theory that was the subject of MUCH derision and
great fun at Dan Lavry's old ProSoundWeb form:
PSW Recording Forums: Dan Lavry => Why longer is generally better for an S/PDIF Digital Cable