First of all, it is not a hobby, it is a number of businesses. And, yes, the IRS expects you to file as many Schedule Cs as needed to differentiate between the various types of jobs.
You included, "artist, seller of raw materials, fossil hunter, gardener, writer, create video, and more. I file under one business." To the degree that you can fit categories together, such as finding materials to create jewelry, that is one business. Your raw materials are inventory.
However, you can't include gardener, writer and video creator. These are all separate businesses and need to be reported as such.
