• MST3K-izations of movies are plentiful. But there's a higher bar to them; viewers expect the commentator to be enhancing a movie that might otherwise be unwatchable, not just adding their thoughts.

• "Directors' commentary" (and "actors' commentary", etc.) audio streams are also plentiful. If someone's opinion on the movie as it progresses would be specifically interesting, then people will want to combine the two.

Many people do post "blind reaction" videos for various series. They're quite popular; many "reaction" channels have tens of thousands of subscribers.

In those, the reaction is the valuable contribution; it can be fun to watch something you've previously enjoyed and see how others react to it.

Now I'm going to get a bit artsy. Games are typically about the interaction between the player and the game and how that player reacts is a significant part of the experience. Let's plays sort of mediate this experience by allowing the audience to see the reactions of the let's player. This is much less powerful, but sometimes the audience actually prefers the less powerful experience. Horrer games are popular to watch because people don't always like being scared (but watching other people getting scared is pretty entertaining). That Dragon, Cancer likely suffers because it's not a game that makes you feel good, it's an intense experience; it's easy to prefer the less-intense, mediated experience. As a result, the sales overall may suffer (and the artists might be frustrated that people aren't playing it 'properly').

It almost needs a new business model. I think we can agree that more games like this is a good thing.

I'm not a movie guy but for some stupid weird reason I love watching what they think about some movies.