Look at the names WWE has built since then, and where they started pre brand unification.
Cena - SmackDown
JBL - SmackDown
Eddie Guerrero - SmackDown
Chris Benoit - SmackDown (won the Raw title, but gained his popularity on the blue side)
Batista - Raw
Randy Orton - Raw
Edge - Raw
Rob Van Dam - ECW
Jeff Hardy - SmackDown
Rey Mysterio - SmackDown
Christian - SmackDown
CM Punk - ECW
Dolph Ziggler - SmackDown
Where they started probably isn't the best measure when you consider the likes of Guerrero, Batista, Edge, RVD, Hardy, Ziggler started on opposite sides. Even a guy like Benoit who was initially drafted to SmackDown initially, made his first appearance on the Raw brand as one of Flair's guys.
But you're right, SmackDown made far more stars than Raw.
Even guys who weren't exactly main event material, were given a far greater opportunity to succeed on SmackDown than they would have been given on Raw. Guys like A-Train, Tajiri and Matt Hardy v1.0 come straight to mind.
Then you have guys like Orton who had all tools to get over as a superstar yet pales in comparison to his peers, like John Cena, who quite honestly aren't as naturally gifted as him. I believe a large part of that was the way his championship push was handled and all his subsequent runs.
So even then, Raw didn't impress me and was quite honestly a drag to watch which is a shame because that's what most Australians had to settle with back during that transitional phase between Dial-Up and Broadband.