[rofws]

I might be wrong, but what you have mentioned as businesses are only mediums to achieve a (business)goal. For eg. - Goal can be 'showcase your expertise on XYZ topic to attract specific kind of people' and the medium would be podcasts or newsletter. That way, if your medium is unsuccessful, you can always change the medium without losing sight of the goal.

[Ptrulli]

Good suggestion and point here. I am currently looking into becoming a subject matter expert on a particular topic of interest, as of now, I feel like I'm not on any topic. Rather I know a little bit about various topics.