Final answer:
The use of 'let' in a top-level scope does not make a variable globally available throughout the script; its availability is confined to the current scope. Hence, the statement is False.
Step-by-step explanation:
The question seems to be concerned with the scope and use of variables in a programming context, particularly referring to the let statement in modern JavaScript or a similar language. When you declare a variable using let at the top level of your code, it is not necessarily global like with the var statement; instead, it is limited to the scope of the block, script, or module in which it appears. Therefore, False: let x = e is not implicitly 'in the rest of what you type,' it is only available in the current scope.