Samsung OneUI has been able to do home screen landscape for quite a long time, I was a Samsung user for a long time (recently switched to Pixel 10 Pro) and remember the screens would reorient continually when I'd turn the phone. I found it useful for me as I have a car mount on my dashboard that holds the phone landscape while I'm driving, but I can see how it can be frustrating for startac4 if he's not interested in that feature.
This can be defeated by changing rotation setting to OFF, so it won't flip the orientation at all whatsoever; that might be a bit inconvenient if you have apps which work better in landscape aspect, but that's the way to stop it continually flipping.