Think of it this way:
You are a witch.
But no one is going around looking for witches, no one is going around suspecting people of being witches.
Sure, you have a herb garden and a black cat, you wear black dresses, and you love going for strolls in the forest under the full moon’s light.
But very very few people would actually truly believe you are a witch. Other people’s responses would likely be “that’s just the way she is”, “oh that spooky goth bitch is at it again”, or even “lol. What are you, a witch or something? Hahaha!”.
An actual witch might see you and conclude that you are a witch, but that same witch might see a non-witch who just happens to enjoy moonlit strolls with her cat, and conclude that she also must be a witch.
Likewise, in everyday life the majority of people aren’t out there looking for people with DID/OSDD, or carefully observing every single person to check for signs of DID/OSDD.
You can be out there with obvious symptoms, and successfully just wave them away as “memory problems”, “mood swings”, “poor time management”, “inconsistent beliefs” etc.
Even people who see you every day, and notice these symptoms are likely to write them off as “That’s just the way they are”, “Maybe they have (insert common mental health issue here)”, or joke about you having “multiple personalities”.
(Of course some people will dismiss these symptoms as “laziness”, “rudeness”, “being inconsiderate”, “wishy-washy”, or other cruel and dismissive explanations.)
Even when you think that your system seems extremely overt, and even if you feel as though at any moment someone is going to realise that you have DID/OSDD... the more likely outcome is that everyone around you has just accepted that those obvious symptoms are “just the way you are”.
(There are exceptions of course.)
Humans want to identify with each other.
The social rules of our species mean that we rationalise phenomena that we ourselves don’t experience.
The result is that “covert DID/OSDD” doesn’t need to be all that subtle in order to protect you.
A lot of people worry themselves over whether their DID/OSDD is overt or covert, not really understanding just how obvious your DID/OSDD can be before it’s no longer covert.
Here a person talks about the differences between overt DID vs covert DID,
and later their own experiences with extremely overt/florid DID:
https://mr-system.medium.com/our-overt-covert-disorder-dissociative-identity-disorder-56693450d758
*Please note that this blog does not have a stance on endogenic systems, but the above link does briefly mention them in a negative way. Please do not click the link if this will harm you.*