Agreed.
There are many, many, many occurrences where literalist transcriptions skip words or syllables that are 'swallowed' in normal speech. IMO this reflects very poorly on the intelligence of the transcriber.
ONE SMALL STEP FOR [static/crackle] MAN -- the cadence clearly implies a swallowed and/or static-obscured 'a'.
I was about to say there was no "static" during "one small step for(a)man", but there is a little bit in the background. I don't think it obscures his voice, though. The audio is of reasonable quality, even if less than perfect. It's just that he races over it. It's an elision, really, but it's still there, like the grin of the Chesire Cat.
The article claims it's objectively decipherable from the audio, but words are subjective, after all is said and done.
When you say "man" it leads off with a "nasal stop" - a little grunt - like "(um)an". "a" is said "uh" - a "glottal stop" - so "fer uh man" is hard to discern from "fer (um)an".
Blame it on Cronkite. Or anybody else in the media. They repeated it wrong!