On a different tangent- what I like about your Stoic project idea is that (putting aside the AI vs human element for a moment) it starts with the problem... and THEN goes looking for a targeted Stoic solution.
This to me is distinct from the usual approach of learning about that kind of stuff- ie starting with reading the literature (the solutions), and THEN going looking for the problems in your life it can assist with.
I think Stoicism (being the practical philosophy it is), is uniquely placed to do this 'start with the problem' approach.
Bespoke, agony aunt style problem solving is very hard to do for dogmatic religions and theory heavy philosophies.
Unlike many religions or philosophies- you don't need to be a full blown follower or devotee to garner real world benefit from Stoicism.
Of course, you only get out what you put in- so any benefits would be very small for anyone limiting themselves to just ingesting quotables (via AI chatbot or humans posting memes on socials etc).
But every great journey begins with one small step right?
Here's something to ponder: perhaps your AI friends chatbot idea is complementary to your idea- instead of it being a competitor?
Maybe his idea of journalling to an AI chatbot would 'warm guys up' to taking the next step (ie your idea of sharing their problems with real people).
Perhaps the leap (sharing problems with brutal honesty with a real person) IS too great for many guys? Even with the relative safety of doing it in a virtual setting.
If so- an AI journalling thingo could be a stepping stone and help create more guys ready to talk with a real person.
Maybe advertising your hypothetical real person service to AI chatbot users would catch clients for your service that like the AI stuff... but get bored of its shallowness and inhumanity- and want more substance and results?