One of the things that confuses me most about endos is how the fact that they talk about "non-disordered plurality" a lot. But logically, if endogenic plurality was a thing, wouldn't it be considered disordered due to the nature of plurality?
Your ego states have to fail to integrate for plurality to happen, if fully integrated ego states somehow split apart, wouldn't that be some kind of disorder too? It wouldn't be considered a perfectly normal and healthy experience at the very least.
(Post was written while blurry and tired, sorry if it doesn't make sense)
The concept of multiplicity without a disorder isn't actually new, and has been speculated about since the 90s with the community existing online for as long as that time, and probably longer given how there aren't offline archives (and much longer given how thoughtforms as a concept have been around in occult community the 1900s).
There's also a simple answer that "not all plurality is ego states" because plurality is a very broad umbrella term and just not everyone thinks of themselves with DID frameworks, but we can actually look at the DSM criteria itself for this, mostly these two:
C. The symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.
This is the biggest one that would exclude even some trauamgenic systems who achieved functional multiplicity. Every disorders has this and it's why you can, for example, hear voices without it being a disorder if it doesn't cause clinical distress or impairment.
D. The disturbance is not a normal part of a broadly accepted cultural or religious practice.
This one would exclude specific types of endogenic systems, like thoughtforms, fictives/soulbonds/people experiencing fictional characters in their body, etc.
We don't have enough research into how endogenic systems outside of thoughtforms form. There is actually research into endogenic systems, but it has to do more with how they are in the present. It's a lot easier to research childhood trauma and then get results for DID than it is to try to predict who will be a system.
There's always a chance that endogenic systems could be a failure to integrate, and worth mentioning a disproportionate amount of endogenic systems we've seen have autism or a developmental disorder so it would make sense, but there's not really enough data to tell. There could always just be an underlying thing to it and my thoughts is that there's just something that makes people predisposed to being plural, hence why two people can go through the exact same trauma and one might develop DID while the other doesn't.
