Unison is a pure functional language. That's important because it allows the whole "big idea" to work: you can change code, commit it to your Unison database and synchronize with your cloud without it ever breaking due to things like "different versions of a type" for example.

This language OTOH looks like TypeScript with seamless access to cloud resources, which while neat, is not comparable to what Unison brings to the table (it may, however, be what people actually want... time will tell).