Ah, I see, you think that just because our brains can handle the idea of metacognition and existential thinking, it must be accurate. But don't forget, our brain's job is to make sense of things and give it meaning, so its natural response is to try to explain what these things are and where they come from. That doesn't mean that there is an answer. As Nikhil alluded to in his essay, belief in existence is a religion of our times. It's easy to forget that not everything can be understood or explained with scientific evidence; some things must be taken on faith.
Just because we can make choices based on our understanding of the world around us doesn't mean those choices aren't predetermined or influenced by electrical impulses or chemical reactions. In fact, the opposite may be true. By taking those decisions for granted, we may be blinding ourselves to the larger implications of what it means to make a choice urRong and whether we have any control over that choice in the first place. So while metacognition and existential thinking can take us on a new journey of understanding, it might be prudent to take a step back and carefully consider our beliefs before we make any concrete decisions. After all, why let our brains get in the way of a good philosophical debate?