She shouldn't be in the past, end of story. She gets her mother killed (she almost has) and she won't exist.
The show is filled with lots of shouldn’ts once time travel is introduced.
She won’t be around if she’s not around to save Barry’s life.
Regardless of should she, she was in the past and already changed things. Who knows maybe what she changed maybe her present worse than when she left it. We don’t know.
What we do know: in our present Barry and his team ARE there and able to protect her.
Again. Living is safer than potentially erasing your whole existence.
We don’t know it’s safer.
What’s safer than being with your super powered father and his team of super geniuses that have saved the world again and again?
There's zero argument that can ever support her living in her own past as a superhero (putting herself in immediate physical danger constantly), Barry should have done this on day one.
No. There’s more than zero arguments. You disagree, but there’s a good argument that, now that she’s in the past away from Zoom, she’s safer until the end game is reached. She could NOT be a super hero. She could not participate in dangerous activity.
And who knows, paradoxically, going back in time was a way TO secure her existence.
That’s two, TWO arguments of why Barry shouldn’t have dropped her back into the future.
What Barry should’ve done is go back before she left and prevented her from going. But then, we wouldn’t have gotten this season (a pro) and/or another flashpoint (con).