I don't mean creating a channel and showing off your expertise in videos, which would be a good topic authority signal in many niches.
I'm referring to your watched videos and comment history. Sounds unlikely but hear me out.
- Youtube and search console login match thus identifying the site owner
- You must be logged in to comment
- Youtube comment and watch history tells Google what your intersts are
- It makes sense that if you watch widget content and have a site about widgets and offer insightful comments about widgets that MAYBE you know widgets?
Could this be a source of identifying authority and knowledge about a topic?