I think you can't make sweeping generalizations about what may or may not work for everyone and that applies to therapy just as much as anything else.

I will say that for me, what has made the most impact has been my relationship with my therapist. If I didn't have the solid relationship that I have with her, I just don't think I'd get much out of therapy. That's just me, though. Others may find other things more helpful or important.

My mom (who I think really does need therapy) doesn't see the value in therapy, but that's her own bias. She has repeatedly said to me that she doesn't see how talking about things that happened in the past can be helpful. If she sees no value in it, of course therapy is not going to be helpful.