Depends if comfort or frugality is the top consideration. Because at different stages in our marriage, those factors impacting the house temperature a lot.
We live in Michigan and it can get cold. In our budget tight earlier days of family life, we'd keep it lower to save money. Low 60s.
Now that we're old and in a better place financially comfort wins out and it's usually kept around 68-71 during the day. 65 at night.