I think it is the result of the reduced copyability of video compared to plain text. This makes it easier to monetize video. Since lots of writers don't have a

I think it is the result of the reduced copyability of video compared to plain text. This makes it easier to monetize video. Since lots of writers don't have a secondary source of income and have to pay for housing/food/loans/etc, they have an incentive to spend the effort to write video scripts rather than essays/articles.