1Some situations genuinely run on how you are seen. A job interview, a court hearing, a first meeting with in-laws: the image matters there, and it is honest to say so.
The claim is only that most of life is not one of those, and that the fear of disrespect is far larger than its actual cost. Keeping the exceptions in view protects the whole point. Any way of thinking that says it covers everything gets thrown out the first time it obviously does not.
Islamic evidence
Uphold justice and bear witness to God, even if it is against yourselves (Quran 4:135). Saying the part that weakens your own case is set as the standard rather than the exception.
“You who believe, uphold justice and bear witness to God, even if it is against yourselves, your parents, or your close relatives. Whether the person is rich or poor, God can best take care of both. Refrain from following your own desire, so that you can act…”
Qur'an 4:135
Psychological evidence
In two studies of American and British citizens, anger, guilt and shame about their country's actions predicted opposition to those actions, and a threat to the country's image changed which of those feelings dominated. Image threat is a real thing that shifts how people respond, at least at the level of a group. Those were survey and experimental studies about national identity, so carry them across to a job interview carefully.
Iyer A, Schmader T, Lickel B. (2007). Personality & social psychology bulletin · doi
Review detail
Why it works. A claim with honest limits is one you can still use when the limits turn up.