Back then, everything didn't center around media hype. This was a proud achievement of the US. There was a sense of national pride and I'm sure Armstrong knew it. Today however I'm sure every sound bite would be scripted.... .. .. .. .. . . .. . .. .. ..
No I do not believe NASA scripted Neil Armstrong's words because the 60s were not a time when those sorts of things were scripted. Public appearance was not as important to organizations or their employees and therefore NASA would have trusted Neil and allowed him to make his own statements.
I would think that the vast majority of the focus for NASA at the time of Neil Armstrong's, would be focused on the success of the mission, and not necessarily the outcome of the scripted words that were said upon completion. If you listen closely you can hear that Neil Armstrong used words that I feel, came from his heart.
In my opinion, when Neil Armstrong proclaimed upon setting foot on the moon that it was one small step for him but a giant leap for mankind, that was his spontaneous thought. He adhered to that until the day he died. I believe he should be given full credit for the witty statement.
Perhaps NASA scripted Neil Armstrong's words when he first stepped on the moon's surface. WHile I don't believe the words were scripted by NASA, perhaps they had a hand in the general thoughts to be expressed. Perhaps they didn't. Either way, so what? The magnitude of the accomplishment should in no way be minimized by some menial question about whether those words were prepared by one person or another.