Although quite a lot of that was due to actor salaries rather than production budget. That was pretty typical. Saturday morning shows tended to keep rerunning the same episodes over and over for as long as they were on, partly because kids were more tolerant of repeat viewing than adults, and partly because the reruns were new to the younger kids who'd just started watching. So "new" seasons would tend to consist of maybe 6-8 new episodes stuck in between the same old reruns. But the second season's shorter length was actually to its advantage. The first season was badly rushed due to the network giving Filmation only 6 months to make 16 episodes, so the production values suffered. Season 2 had more time and money to devote to each of its 6 episodes, so it was done with more care, with better, less repetitive animation and better voice acting from Shatner and Kelley.