The Flintstones also did a bit of a pivot too - they realized they were picking up more kids in their audience so they shifted from an adult sitcom to more of a family friendly show. The later episodes do have a bit of a different feel from the earlier ones.

Also, many of the later reruns on The Cartoon Network, etc. ditched the original laugh track (and good riddance), and that also gave the show less of a sitcom feel.