I regularly watch Let's Plays of video games, but rarely do I watch an LP of a VN.
For me, visual novels are something I prefer to experience independent of any color commentary or personality. If it's something I've read before, that's obviously a non-issue, but then I feel like I could be using that time reading something new rather than treading over old ground. The main thing is that I just simply haven't found a youtuber entertaining enough to really want to watch someone else play a VN.