The film (to me) wasn’t necessarily about Barbie coming back to Barbie-land to see the Ken’s running the place and that somehow wasn’t right.
It’s more about finding who you are instead of being told who you are… it shows the difference between Ken’s running the place because they have been ignored and neglected by the Barbies so it’s a quick grab for power because they realise they are more than that… the Ken’s realised that their day doesn’t revolve around barbie’s anymore… they realised that they don’t need to feel good about themselves when Barbie says “hi” to them. The Ken’s realised that they didn’t know what they wanted but the just wanted to be heard and have a voice.
Barbie realised how the real world was showing some sexism and wanted to change that however it felt impossible… upon returning to Ken-land, she returned in a sensitive state realising that Earth wasn’t how she imagined and couldn’t see the Ken’s point of view until the end of the film.
Barbie-land was taken back by the Barbies however they had a few Ken’s in power working as a team.
So the film is about extremes and both woman and men fighting for that extreme until the end they find a balance.