Things are getting better. I was aware of them, but jupyter is the 600 pound gorilla in this area.
I wouldn't use observable, as you are tied to their web service, and I've had too many companies close to use such a service for important data. Pluto is promising, but (I believe?) Only supports Julia, which is growing but still not that popular, or known.
You’re not paying attention to the space but recalculating notebooks are gaining popularity.