The entire point of free-will is not stepping in to stop you idiots from killing yourselves, dude. Likewise, the point of believing in humans is believing that they will overcome these issues, even if - or especially BECAUSE they murder so many of themselves, they eventually learn what is bad for them. A mortal can only think of things that happen in their own lifetime, and make guesses at what comes beyond. An immortal being who can see through time can view change gradually, and guide it there.
Tanya's philosophy is extremely hypocritical.