Where Lost in Space was concerned, Fox--more than Irwin Allen--promoted the idea of a Lost in Space cartoon (by 1973, LiS had earned Fox a pretty penny in syndication), but the approach was doomed from the start, by replacing all original characters except Smith (voiced by Johnathan Harris), dumped the Jupiter II in favor of one of Hanna-Barbera's endlessly recycled rockets, and attempted to play up the Smith character, but the screenwriters were just plain inferior--even compared to many of the sub-par writers who cranked out scripts for the original series.
As part of The ABC Saturday Superstar Movie, Lost in Space was one of many pilots, but it--similar to the majority of specials--failed to be picked up, the exceptions being The Brady Kids & Lassie's Rescue Rangers. Hanna-Barbera's Lost in Space pilot was awful, and its no surprise that it failed to sell, with such terrible animation, nonsensical plot and sharing not a thing which made the original series popular (IOW, more than Dr. Smith and the Robot).
Its purely a train-wreck watch.