Check out the `--shutter` option for `libcamera-vid`, it allows you to tweak the camera's exposure time which might help with the screen refresh banding. `--shutter 60` sets the exposure time to 60ms, which might be a good starting point.
EDIT: Ah, actually the unit is microseconds, so `60000` would be 60ms
EDIT: Ah, actually the unit is microseconds, so `60000` would be 60ms