I do wish that JS had more builtin syntactic sugar around generators (and particularly async generators). They would be a lot more convenient and syntactically cleaner if most of the Array builtins could also be used for iterators. For async iterators the builtins would need to leverage the promise builtins as well, so you could to something like:

  const result = await asyncIterator.map(doSomethingAsync).reduce(asyncAggregatorFn)

Without ever having to load all of your data into memory.