My DD friendship group is like this.
I look at their watsapps periodically (they know and is a condition of using).
There is often a lot of stuff about coming out. I don't think any of them ID as straight or 'cis'. A couple have changed names at school.
In general I don't think there's any harm. They are growing up and trying to get to grips with their place in the world and society and their social groups etc.
I would worry about medical intervention.
The other thing that was bad was one of her friends forwarded her a thing saying on a certain date transphobes had organised to go out and kill 'trans kids'. The other child was messaging DD saying how scared they were etc.
That sort of stuff is obviously concerning.
And I mean anyway. They look like bogstandard 12yo school girls.
How this kid thought the organised murder gangs were going to tell which children were trans in anyone's guess.
The narrative around 'coming out' also seems to be seen as something that could make your parents turn on you etc.
There's a definite feeling that fear/ making them feel alienated is a thing but where posts like that originate I have no idea.