This is only touched on in passing, but I think editing is the real missing link here. When content was gatekept by publishers of various sorts, they wouldn't let anyone just ramble on for as long as they felt like. When anyone can do it with no constraints, well, a lot of it is going to be crap.

Producing good work is hard, and part of what makes it hard is not the production of "raw material" but the cutting down of the bad parts and the distillation of the good parts into a more concentrated form.

When I was in college I took a class where we had to write a weekly one-page summary of that week's readings/research. It was much harder than it would have been had there been no length limit. It's easier to make a three-hour podcast than to make a one-hour podcast.

The antithesis of this is regular 30 second sound bites throughout the day depending on whatever agenda the media is spinning at the time.

In the UK, almost every radio station runs these regular news bulletins and they are all indistinguishable from one show to another. Politician/celeb/business person says, blah, blah, blah until it's permanently embedded in your skull and becomes yet another fact that can not be challenged.