

Depends on what you call a show. A good contender is the German TV show “Unser Sandmännchen” (Our Little Sand Man). It is nearly as old as there is a TV program. It shows a little “good night” story each evening for little children using animated puppets.
It started 1959, is still running daily, and so far there are over 22000 episodes.

Not unexpected when they share certain common training sets. E.g. you can expect them all to have “read” Wikipedia and similar information sources.