Hypnotherapy and related is only as useful as the content and meaning and applicability communicated with the unconscious.
Meaning it's basically an art-form.
The therapist must clearly understand the specific core issue (there are thousands),
and address it in a "language" and method comprehensible to the client's unconscious mind,
and define a "cognitive data base" for solution analysis,
and offer a permissive resolution axis,
and without defining a solution (external solutions are nearly always faulty and eventually fail),
and being very careful of the "negative word" trap (don't, not, annoyed, mad).
This is after all the hiccups and missteps just trying to get one into a receptive trance state.
Hypnotherapy can be kinda sketchy, there's no universal 'quality control' like with pills.
Properly addressed though changes 'keyed' by a good therapist, created by one's own unconscious mind, are amazingly fast, creative and very durable.
_________________
(14.01.b) cogito ergo sum confusus