Most movies made today are still 1h30+ long, and I'm pretty sure all of those didn't come up with incredible stories that really warrant that length of time investment.
Movies could see a renaissance once we accept they can be any length, including 45min if that's all it takes to properly tell the story.
For books it's all the more obvious when we sometimes see a succesful blog post blowing up into a full blown book with no additional insight.
The issue is probably monetization and how to sell short content. I think it's hard, but also don't feel like throwing my time through the window as a result.