Your interpretation of the title is not supported by the article’s content. In fact, you’re agreeing with it.
"That doesn’t mean that modern whistled speech is a vestigial remnant of those protolanguages, Meyer cautions. If whistling preceded voiced speech, those earliest whistles wouldn’t have needed to encode sounds produced by the vocal cords. But today’s whistled languages do, which means they arose later, as add-ons to conventional languages, not forerunners of them, Meyer says."
Did you think that passage was a total non-sequitur? Are they cautioning you from believing something you would have no reason to believe? Or do you think they were aware they had unduly created that impression.
I suppose if I say "we shouldn't assume people who comment on HN posts are sad, lonely, and grumpy" I'm not being offensive or disrespectful. After all, I never said outright that anyone was any of those things. On the contrary, it actually says the exact opposite
It's a trick of language called insinuation.
So identifying the minimum requirements for comprehensible, yet sophisticated, communication by sound would possibly shed light on what paleo-speech was like...