Honestly, the most conservative show I can think of is “Leave It To Beaver”.
The family sitcoms of the past such as “Leave it to Beaver” are all conservative compared to what we see on TV nowadays.
All of those shows of the past portrayed family values and did not push the bizarre or immoral and bad behaviors which are pushed on TV nowadays.
And remember a mindless show such as “Gilligan’s Island”? It was a mindless comedy show. It was good for some laughs but was not pushing any agenda.
Can you imagine “Gilligan’s Island” today? My God, do you think that Ginger and Mary Anne would be roommates in their own hut? Would the professor always be trying to get in their pants? Would Gilligan be the obligatory homosexual character???