2) it is hard to discuss many (if not most) personal issues in personal or in group meetings. Suicidal thoughts, depression, life advice - you cannot simply go out there and discuss all these during your first/tenth meeting with a person in private.
This discussion started not because your product idea is bad, but rather because your pitch included trying to tell us that what this Danish group has been doing is not scalable, even though they are doing it since decades with great success. This felt like saying it is somehow the wrong approach.
I think you can add to society with such a chat app, but there is a lot of indication that quality personal interaction is superior, and there are many many groups, even anonymous consulting etc, who have tackled these issues for decades! That clearly is scale, look at AA.
For example, one may also say that non anonymous and close connections, the opposite of what you offer in your app, is precisely the point of this Danish initiative, and your app really targets different issues. In that view, your comment seemed rather flippant. When pitching your app, you probably avoid seeming ignorant of the actual issue at stake.
Best of luck to you