Having a “disconnected personal brand”
Just an observation from some gaming youtubers I watch — most of them have what I'd call a disconnected personal brand.
I don't think this is even restricted to gaming youtubers, let alone most youtubers. But many of them make their youtube channels niched around a certain hobby (i.e. gaming) but over time you learn more about who they are. And they might be like a car salesman or something random.
But then since they have a ton of subscribers, it starts to impact all other areas. For example, subscribers might just go and buy from the car salesman specifically.
One particular example is a van life duo selling Chai Tea. People who love their can life vlogs are (practically) the only buyers of their tea leaves.
Maybe this could be adapted to help build your own brand — but I haven't figured it out that far yet.