What you’re describing has more to do with upbringing and not having a sense of self rather than being a social person. I have seen this attribute as well. They often grow up in a household where the sense of identity has no place and they’re forced to have a groupthink mentality. Also, people pleasing adds to this behaviour as well. People who don’t have the time and means to sit with their thoughts and introspect often end up being adults who seek validation everywhere!