This is largely due to a crisis in the field in the late 70s/early 80s when several studies demonstrated that talk therapy had outcomes no different than no therapy. In both cases, some got better, some got worse, some didn't change. CBT was a direct result of that, prioritizing and tracking positive outcomes, and from CBT came a lot of different approaches, all similarly focussed on being demonstrably effective.
Talk therapy isn't a cure-all, but it's definitely more results-oriented than it was 50 years ago.