I don’t think it’s false, much less obviously false. On one hand I have my personal experience about it, on the other you can see there’s only a small range in the “I want a conversation” scale where they want it enough to ignore the nonverbal signs that the person doesn’t want to talk but not enough to ignore the verbal ones.

Well, I don't see a "small range" at all. It's the opposite, extroverted pleople usually have better social skills than ones with social anxiety.