Polishing the wording for waitUntil non-streaming error (#11740)

see https://vercel.slack.com/archives/C02F56A54LU/p1718616636500349 for
more context

errors/wait-until-non-streaming.md

@@ -2,15 +2,13 @@
 
 ## Why This Warning Occurred
 
-The [waitUntil](https://vercel.com/docs/functions/functions-api-reference#waituntil) method allows you to enqueue asynchronous tasks to be performed during the lifecycle of the request, and these tasks can continue to resolve even after the response has been written.
+The [waitUntil](https://vercel.com/docs/functions/functions-api-reference#waituntil) method allows you to enqueue asynchronous tasks to be performed during the lifecycle of the request, and these tasks can continue to resolve even after the response has been written. This is possible because `waitUntil` takes advantage of [streaming functions](https://vercel.com/docs/functions/streaming#streaming-functions).
 
-This is possible because `waitUntil` takes advantage of [streaming functions](https://vercel.com/docs/functions/streaming#streaming-functions).
-
-When `waitUntil` is used in a non-streaming function, the behavior is limited and the response is delayed to be written after the enqueued asynchronous tasks have been resolved.
+When `waitUntil` is used in a [non-streaming function](https://vercel.com/docs/functions/streaming#non-streaming-functions), the behavior is limited and the function will delay the response until after the enqueued asynchronous tasks have been resolved.
 
 ## How to Fix It
 
-To take advantage of waitUntil without compromise, all you have to do is explicitly opt-in your functions to support streaming:
+To overcome the limitations of `waitUntil` with [non-streaming functions](https://vercel.com/docs/functions/streaming#non-streaming-functions), you should explicitly opt-in your functions to support streaming:
 
 ```js
 export const config = {