I don't know about you but if you have ever uploaded any Youtube video, you'll see in the Creator Studio that Youtube clearly says "tags have a minimal effect on helping others find your video", and I imagine that would be the case for the majority of blogs as well. That is, the ones that choose to utilize tags in the first place.
How does this have anything to do with AI though?
I'm curious if he's really click the tags in Youtube

I think tags is helpful in Twitter because someone tweet can become popular due to tags usage, not in Youtube. This forum, I don't think it will work many members already fine with the current interface and feature, they're prefer just google some keyword they interested and add Bitcointalk to make you find the thread you're interested/searched.
Yeah, tags is just a structured data and not related with AI, tags isn't a machine learning. I think most people think anything in digital is AI.