None of these treatments has a 100% success rate. You can try EMDR on Youtube and if it worked all the time, psychiatrists would be out of a job.
And I am well aware of the placebo effect.
But just because something is not provable or falsifiable under current scientific knowledge, it does not mean it is neccesarily quackery, there's a Venn diagram there where some things may be effective.
Automatically discarding something that even occasionally gets results, because it doesn't fit current "knowledge" is the height of arrogance.
Do you mean unproven instead of "not provable or falsifiable"?
Something not being falsifiable would mean that we can't detect if it's doing anything even if we tried, which doesn't bode well for its effectiveness.
Sorry, I should a put a source: partner is a therapist.
Edit: autocorrect changed psychotherapy to physiotherapy.