Not as rare as you might think. EMDR is not widely accepted or recommended as treatment for persistent/long term complex trauma, when it is, such treatments are modified to fit a broader treatment regimen. Even then, it continues to be a controversial form of treatment for trauma.

This isn’t to say that people should not consider EMDR, but if they do, don’t just seek out an EMDR practitioner and expect a quick fix, but ensure the practitioner is trauma-aware and skilled in adapting treatment to the specific needs of patients with trauma histories, and it’s part of a broader treatment plan.

EMDR is well accepted and not controversial.

https://www.ptsd.va.gov/professional/treat/docs/mhp_veterans...

You're confusing CPTSD and PTSD. Your link talks about EMDR for PTSD, not CPTSD. The post you're replying to is talking about CPTSD. They can be quite different.

As the sibling pointed out, C-PTSD and PTSD are not the same thing. When EMDR is incorporated for C-PTSD, there are some aspects that are modified based on the trauma history, and some cases where EMDR cannot be attempted until dissociation issues have been addressed.

It is this need for modification and the prerequisite work (sometimes the long/hard kind of work) that makes it less clear-cut as a treatment for this form of trauma.

The EMDR practitioner I worked with made me aware of this as did my regular therapist, and most C-PTSD-aware EMDR info you can find online will also explain this distinction and the necessary modifications/prerequisites.