The thing with therapist support for teens is that it requires the teen to have to go to their parents and ask to be taken to a therapist (not to mention the cost of the therapist). A teen having an AI bot trained on things therapists do/say and techniques they use could give teens an outlet for issues that they benefit from simply venting or talking out, but aren't serious enough to have to go through all the steps and vulnerability/exposing yourself needed when it comes to asking parents to take you to a therapist.