First of all, I thought this was a great movie! What I'm going to talk about isn't even about the central message of it. In terms of spoiler level, I'm going to make general statements about the story, and cite a particular detail from pretty early in the movie.

Early in the movie, when the emotions are checking on the "islands of personality," and islands like "hockey" and "friendship" are portrayed as booming—like, they could not have been animated bigger or more full and lively—the "family" island is, as far as I can remember (I haven't found a picture online) just three colorless figures standing together. It could not have been drawn more lifeless and devoid of content, activity, or significance. The sight of this island draws a quick "yikes," and then the movie moves on. It never highlights, comments on, implicates, or judges one way or another, the fact that Riley's family relationships have no present significance to her. Presumably she does not have meaningful family time or emotional closeness with her parents, like she did when she was younger.

Caveat: My kids are 8 and 10. I've never parented a teenager, though I have been one.

The fact the movie makes a very clear statement about Riley's "missing" family/home life, and then does not follow it up, is fascinating, and powerful, to me. Even in the first movie, different viewers saw different things. To some, the movie was about parental emotional neglect and childhood depression. To others, just a "normal" blip in a child's life. It raises questions about what is normal. Because a majority of people (I believe) do face some childhood emotional neglect. The movie very clearly portrayed the parents as emotionally stunted, and not very emotionally present/available/intelligent/attuned to their kid. It didn't focus on whether this was good or bad, or causative, or normal. While most of both movies takes place inside Riley's head, and we don't know how typical or unusual the heroics of Riley's emotional characters are, Riley is not an average kid or an every-kid; she is exceptional in school, for example. Her family is a particular kind of family: white (with the associated cultural emphasis on individuality and career, de-emphasis on family ties); one kid, who is gifted/talented; parents working and kind of doing the minimum as far as parenting, while passing as typical loving parents.

The significance of the ghostly, pea-sized family island seems to fly under the radar, in commentary like this:

The fact that Riley's Friendship Island has grown larger and "more important" than Family Island isn't necessarily a big surprise. After all, the change aptly reflects the way many teenagers feel as they grow more independent and invested in their friendships.

I think there is something more going on here, and the creators of the movie know it, they just aren't focusing on it.

Because I can imagine a family where there are significant, meaningful, impactful relationships between a teenager and their family members: parents, extended family, siblings, chosen family. I've seen depictions of it in media, in some cases where the characters have those values as part of their cultural background. But it could just be parents who stay emotionally connected. Yeah, their kid isn't going to tell them everything, but they should be able to go to them when they need to. What the movie doesn't spell out is, Riley's anxiety around belonging to a group, her fragile sense of self, the shame underlying her anxiety... is to some extent created by her lack of connection at home that makes her feel safe, secure, and wanted. At least, that's my interpretation.

The family I grew up in went on trips (summer vacations, etc.) when I was a teenager, and had "family time," but daily life was so disconnected (I spent most of my time in my head, in my own personal hell), that it wasn't meaningful to me. The things my parents wanted me to identify with as part of identifying as part of the family—certain national and religious heritage, etc—were presented in such a self-important and ego-based way, that they also didn't end up being personally meaningful to me. But I know this is not the case for everyone on the planet.

Somehow I know that "family" can provide a lot to a person, in terms of spirit, soul, psyche, purpose, belonging, love, friendship. Not just help shape a kid into a "good person" in the first 12 years, and then clothe and feed the kid and ensure their academic success, after that, which is what my parents did. Seeing that family island helped me come to terms with that lack I've experienced in my life, in that department, despite being raised in what would be seen as a normal, "good enough" way.