1. We think it's very scalable. The value of attention has flipped - you used to get bored and need to fill your time, now your time is the last scarce resource, so it makes sense to pay to use it more wisely. We see early adopters doing this happily now, but we think it will become the norm.
We also think it will be good for democracy. The incentives of ad supported social media encourage clickbait, cheap outrage, and hyper-partisanship. Subscriptions reward thoughtfulness and deep value.
The one thing I worry about is too much exclusivity. If we landed in a place with really high subscription prices and only the privileged few getting access to good information that wouldn't be ideal, but that is avoidable.
2. Mostly they will have to change. Some will be successful.
3. The new model is readers paying writers directly. The difference at internet scale is that you can reach everybody in the world, and therefore you can be more successful with a much more specific topic/audience. Also because of software, you can start doing it as an individual writer in an afternoon.