Nick, do you actually know what a dualistic mind is? Your repetition of the term and inability to think of alternative expressions suggests a rather robotic lack of understanding of the concept, which you are spraying around without much care for accuracy.
Dualistic thinking, or the “egoic operating system,” as my friend and colleague Cynthia Bourgeault calls it, is our way of reading reality from the position of our private and small self. “What’s in it for me?” “How will I look if I do this?” This is the ego’s preferred way of seeing reality.
As clear as a bell, that's you on the forum - always self-promoting and desperately keen to be seen to "win". Not much point criticising dualistic thinking if you routinely engage in it yourself.
Also, I am not convinced that people consistently retain modes of thinking throughout life. Certainly age tends to make one more "philosophical". To that end, I am not convinced that there is a single "most important question". Rather the importance of questions tend to depend on the stage and state of one's life and circumstances respectively.
Your nominated most important question - "Who am I and what is my place?" - is one that largely concerns the young and old. Once the young leave the nest, very often the most important question is, "How do I survive?".
That challenge to one's survival brings what "anti-dualist" theists derisively refer to as egoistic thinking - “What’s in it for me?” or “How will I look if I do this?”. These are the questions of young people trying to establish themselves and set up their lives in ever more populated, and consequently competitive, societies.
It is only with the space provided by childhood, indolence, retirement or relevant work that people have the opportunity to ponder the biggest questions at depth.