Dave, the Gummi Bears was a Disney production -- and a pretty good one at that. Perhaps you meant to say Paw Paw Bears (from The Funtastic World of Hanna-Barbera) or -- gasp! -- The C.B. Bears. And H-B was only partially responsible for The Smurfs, which may have been their last (and NBC's next-to-last) big Saturday morning hit.
I will add to my comments from a couple of days ago: You can blame the networks and the production companies for less-than-inventive programming, such as following the latest trend or hot primetime star to build a series around (The Gary Coleman Show, It's Punky Brewster, ALFTales, Kid 'N Play, ProStars, Hammerman, or New Kids on the Block anyone?), you can blame cable for today's oversaturation, and you can blame the FCC for the over-regulation which eventually led to the E/I rules that got the networks and stations out of kid's programming for the most part.
But, unless there's some licensing rights issues involved (and there may be a lot that we don't know about), there's no reason why Dungeons & Dragons, for example, has rarely been seen since its original run on CBS ended more than 20 years ago. Yet, mindless drivel such as Power Rangers and Yu-Gi-Oh! continues to run in some form.