The reality, I think, is that most people fundamentally don't like to read, and that reading more than a few paragraphs is rapidly becoming something akin to a chore for the majority of the population. Watching a video, on the other hand, is an entirely different experience and one that more-or-less comes naturally to human beings, no matter their education level or cultural background.
I run a Substack myself, but I've increasingly become convinced that text-first platforms don't have a mass-market future and at best, will exist as a niche thing. Instead, I think video-first platforms will gradually solve the advantages text still has over video – for example, search and scrolling. As such, I'd recommend any writers/content creators seriously consider adopting a video-first approach, or at least a hybrid one.
Also see a recent discussion on this topic: https://news.ycombinator.com/item?id=38924022