It's about time somebody speaks up on this!
Though the problem: people watch stuff on their phones these days. And it's easier to hold the phone with one hand than with two. Upright. The aspect ratio matches the viewpoint. Sucks for all of us who wants to really see things as they're meant to be seen, like we see the world: with two eyes. Beside each other. Wider. Panorama. Maybe if phone manufacturers made rotation automatic, both when you record something and when you view it...
-cd-