Functionally, You've changed two major genres of entertainment: Anime and Video Games.
No DB means Shonen series are completely changed.
We may see more Sports/Sci-fi in the genre, since Series like Slam Dunk, Ashita No Joe and Gigantor are still around.
Since no DB isn't likely to have an impact on martial arts mangas like Ranma 1/2, they may draw more influence from Fist of the North Star and Jojo's Bizarre adventure.
Which in turn means it might be harder to bring them over to the US if they're significantly more violent and bloody.
Kinnikuman is still around, and it's considered to be another major influence on the genre, so it's possible that it may fill the niche as the super-popular martial arts, technically wrestling, manga with comedy.
Although Brocken Jr might make it a bit of a hard sell.
So basically, the four big Shonen series that may influence people are now Fist of the North Star (emphasis on Manliness), Jojo's Bizarre adventure (strangeness), Kinnikuman (the parody/comedy and martial arts/wrestling) and Saint Seiya.
No success means he's never approached by Yujii Horii and the Dragon Quest/Dragon Warrior series isn't likely to be as popular.
It's still the first of it's kind and a major influence on the JRPG genre, but without Toriyama's artwork it won't get the boost in popularity like OTL. Might still lead to a successful series, or without that popularity to bank on, it might just wither away against Final Fantasy.