> and then they get better - no matter what treatment is provided
I don't know what experience of therapy you've had in the past, but this is typically not how it works. People get better when a treatment is applied that is suitable to them as a person and the context, not sure where you'd get the whole "people get better no matter what treatment is applied", haven't been true in my experience.
I'm only reporting what I heard in my intro to psychology class years ago... Still, this is more revision to a mean applying. There are for sure treatments that are better than doing nothing, there are also treatments worse than doing nothing. But in general people tend to get better after a time. (they often get worse again in a few months, but this was not covered in class).
https://en.wikipedia.org/wiki/Dodo_bird_verdict