E.g. an instance of List(Boolean) can be created, and it correctly pre-assumes that all elements are Booleans in the UX.
There are two parts: the prototype allows now to create, edit, and maintain typed lists, which are a generic type.
So in a specific, bespoke way it is possible to create typed lists. This can be, for example, seen when creating a type and when we create a list of keys.
What is not possible is to create an instance of any generic type, not just of a specific generic type. I have created T297244 for that. Given that, we can close this as being only about Typed Lists. Agreed?