heads up anti-endos. the DSM and ICD both support the existence of non-disordered plurality (which obviously won't be diagnosed as a disorder because it ISN'T A DISORDER). so doesn't IFS therapy.
I had a 4th screenshot (for the IFS therapy part) so I'll have to go re-find that.

actually there is scientific/medical evidence of endo systems, it's just different than DID/OSDD-1/P-DID systems (actually featuring an actual, real source)