Why can't I rotate a video?

Come on... This is getting ridiculous. iPhones often get the orientation confused and you end up with a landscape video in portrait orientation. Not in either the iOS app or the macOS app is there an option to rotate a video. IT'S SUCH A BASIC THING. How many years will it take to fix this? I shouldn't have to use iMovie to fix this. I don't understand what's going on.