I checked “very important”, because we need occasions where we can get to know one another. And, beyond that we need to get to know one another on a faith sharing level, not just social.
It is hard for me to understand when people say they have been with a parish for a long time and don’t know anyone. Surely there are occasions that can be attended where it is possible to get to know others? Coffee and donuts after Mass, adult education, bible studies, Knights of Columbus, Ladies Society, faith-sharing groups, and many others. Not every parish has all these things, but they do have some of them.
Help is needed in CCD and other areas of parish life. These are all ways to be in community with our fellow Catholics.
In my parish, those who are able to attend daily Mass together over the years have formed community. We all know about it when one is sick and may need a visit at the hospital, or a telephone call. Many stay for a Rosary after weekday Mass, and this is another way to form community and get to know people.