For video you typically set shutter speed to half a frame. The most common frame rate is 24FPS, so you get 1/50 shutter speed. It’s lousy for a photo, but good for video , since you want motion blur, so that the video isn’t janky. You control light through ND filters and LED/tungsten lights, not through shutter speed, since shutter speed affects motion blur and you want to make that choice independently of exposure.
120FPS is good for sports or wildlife, but those are special. For normal stuff, 24FPS is good. And even with wildlife, you’re probably not recording at 120FPS all the time, only during quick action. Otherwise you’re just wasting space on your memory card with identical frames. Battery as well.
