What was the point of this show?

Nothing particularly special as such, only that they were a somewhat upper-middle-class family, well-educated & basically decent people who nonetheless had their share of problems & sorrows, just like most people. It's a life that may seem far away & too privileged to younger viewers today, I'm sure; but it was reasonably honest, with a touch of soap opera to be sure, but also with real emotions. An unjustly underrated & neglected TV series, it was popular with many because they could identify with the Lawrences. Of course, the middle class in general was still thriving & upwardly mobile then ...

At one time upper-middle-class families didn't discuss any of their problems in public. Everything was swept under the rug. Pregnant daughters, drop-out sons, and drunk relatives were only discussed in hushed tones behind closed doors. 'Family' provided at peek at an upper class family that had to deal with issues that affected everyone else.

A representation of a “modern” 1970s which I would compare with This is Us (2016). “Controversial” topics of that time were dealt with - divorce, sex outside marriage, female characters had careers, the parents were accepting of their kids choices.