Let's back up a lot of steps; you're deep in proposing a solution
when you've not even explained what problem you think you're
solving. So control question, which I hope will start to expose
the assumptions:
Why do you think its important to know that a snapshot of a
variable has occurred?
From the JEP:
"In addition, a |Snapshot()| operation that captures the current set
of inheritable scope locals is provided. This allows context
information to be shared with asynchronous computations."
As the provider of the scoped variable, I'd certainly like to know
that my scoped variable is being passed into a new scope.
Let's try again: why is that important? What decisions would you make
differently if you had this information? What benefit would come from
those decisions?