Rugrats - "Rugrats" was cancelled to produce more episodes of the forgettable spin-off. Klasky Csupo workers have even said that they would have loved to have gone back to the original show, but Nickelodeon cancelled both shows.

It might be unpopular opinion, but I think this was for the best. “Rugrats Gone Wild” was dangerously close to getting the series to Jump the Shark, and even though All Grown Up wasn’t as successful as they wanted, it still is preferable over running a landmark series for the network into the ground.

TL;DR, at least they didn’t pull a "Fairly OddParents.”

I thought it was fine as a one-shot episode. Turning it into a series was basically a one-way ticket to losing your demographic, and cancelling the old show for more of this rubbed salt in the wound.