1) Written reviews can still be done (I don't want them stopped) but video reviews can augment them in a good way
2) Text captioning can be added to videos for the audio impaired
3) Blind people can't see text or video... so they want audio anyway... and a video can provide the audio in addition to a screen reader
For this particular review, of a hardware device... showing the physical buttons and the items on screen in a video makes it so much more crystal clear. I'd certainly not want to see a video report of the latest kernel function on the kernel page. :)