That is a popular misconception, and is probably why some people hold these prejudices. The trans people that are often seen in the media, at least in my country, are the ones that do not pass well or well enough to be stealth. Since they cannot hide it, they put it on the table, so to speak, for everyone to see. They want to be activists, are motivated by fear, wish to be famous or just need to be heard in order to feel like they exist.
There are lots of other trans people in society. They are cashiers, mecanics, doctors, bus drivers, etc. They are invisible, living stealthily in cis-culture. Opinion about trans people and their need to inform others about their misfortunate birth defect is based on a pervasive idea that they cannot utlimately pass. Only noticeable trans people exist in people notion of transexuality, while stealth trans people are, for all intents and purpose, cis-integrated, and do not feel or need to disclose what was.