I saw a lecture on psychology 101-- I think it was the free online one from Stanford-- where the professor said the main benefit of talk therapy is just having someone who cares about your problems for 45 minutes.
So he what he is doing is therapy.
So he what he is doing is therapy.
The main benefit is having someone trained to listen for specific symptoms based on what you talk about and to develop treatment strategies based on what you discuss and symptoms you experience.
I wouldn't reduce it to "having someone who cares about your problems for 45 minutes." It's more like "talking about your problems for 45 minutes to someone who can recognize which ones are rational, which ones aren't, and can discuss with you how to mitigate the negative effects of your own irrational thoughts."
The cognitive behavioral therapist has to assume the human mind works a certain way, suffering is caused by "irrational" thoughts, and therapist is somehow more "rational" than their clients, so can help their clients be more "rational" like the therapist. These are some big assumptions.
For more info on therapeutic factors, see https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4592639/ obligatory clickbait: you will be surprised!
We don't have deep conversations about theory of function, but the peripheral mentions that creep into our conversations seem to point in this same direction.