Disassociation can be a useful thing to be able to do, sometimes. Under certain circumstances you can be better at dealing with dangerous, stressful situations, for example.
It's generally maladaptive but there's a reason the brain does it.
I have a dissociative disorder (DID) and it is definitely maladaptive sometimes. Sometimes I can be the only one not completely panicking in a situation and bring it under control. But other times I don't pay enough attention to things I need to fix quickly because I just put it away and forget about it. It's probably not just dissociation that does this, but dissociation does somewhat enable it.
There's quite a few definitions of dissociation including mundane "forget details of your daily commute" to "blanking out to a wall" - I'm talking about structural dissociation which is more that the mind heavily compartmentalizes into parts to adapt to vastly different situations like war, random violence, trauma, or overwhelming situations
Obligatory PSA that "the theory of structural dissociation" (as published by did-research.org) is not very accurate in many respects, even though the concept of "structure dissociation" itself (as in the brain compartmentalizating/partitioning itself to separate incompatible information) is still a true thing. (I hate when phonies repurpose the names of true concepts to pass off a bunch of fake ones.)
I'm mainly talking about stuff like: the maximum age supposedly being 6–9, the strict separation into "ANPs"/"EPs"/etc, and stuff like that, being unsupported at best. I do think disorganized attachment itself is one of the more plausible theories for how structural dissociation happens, but I generalize it more to any incompatible information instead.
I fully agree - ANPs/EPs especially really don't hold up in practice. It seems capacity to dissociate might be correlated to the trait of suggestibility, and that's how I personally think about it mechanistically. Personal experience and all, but I keep a lower profile here!
It's generally maladaptive but there's a reason the brain does it.