So if she's a puppet that can't really change things for the better, why this enormous thread with so many people gushing over her?

If she was just another paper pusher and camera model in a world filled with them (like you seem to be saying), her death isn't one of any significance to humanity.

If she was someone who could have used her influence to change things for the better, like Diana would have if she'd been alive - if the Queen was someone who could have done that and didn't, because she didn't want to risk her position, then the anger in this thread is justified and deserved.