> Why else would someone be so anxious about how others see them?
The scientific consensus would tell the author that judgement in humans happens already the moment they see a person and it is immediate, even if the person not doing anything:
https://www.nature.com/articles/srep40700
>across three studies, we find that first impressions [...] made from thin slices of real-world social behavior by typically-developing observers are not only far less favorable across a range of trait judgments compared to controls
Edit:
Okay this was completely misunderstood. My point was that the "normal" people in the study immediately internally know if to like or not like a person. Hence why first impressions DO matter the most. Which is why I simply disagree with the argument in the OP that anyone has control over their perception.
You also cannot win people over if the most respected person in a group dislikes you. The others will follow boot.