You seem to be answering a different question, although the OP seems to agree with you, so now I'm confused about his concept.

The YOU that you're discussing is the sense of self that's in contrast with other people, particularly in society.

My question to the OP was about the YOU in context with his concept of YOU noticing one's MIND. The examples you gave wouldn't apply to the YOU that is distinct from your MIND. Your MIND wouldn't be telling you that you're an extrovert while YOU say you're an introvert.

Fundamental, outward facing beliefs that are about the self that projects to society are generally consistent between YOU and your MIND because if they weren't, you just wouldn't project that belief.

From what I gather, the answer to the nature of "you" lives in the crossing of genetic characteristics (what is entirely innate to us) and the patterns we've absorbed throughout our lives (what is learned into us).

From what I gather, that's the description of MIND in the article. If that's the description of YOU, then I'll turn the question around and ask, what is MIND?

Could I ask that you read the article in the OP? I've been down a rabbit trail with you before where you're talking about something that's not in the article. There's no mention of a human soul in the article that I saw. It's not a religious piece unless he's tracing mindfulness back to Buddhism. Even then, not all Buddhists believe in the concept of a human soul.

Some background. When people talk about mindfulness, they're generally talking about observing one's thoughts. The thoughts are generally depicted as MIND. But then there must be an observer of these thoughts, generally depicted as YOU. Who is this observer?

The reason the question matters is because there's a sense that YOU who are watching these thoughts is the knowing observer, particularly in western culture. To my understanding, in eastern cultures, the idea of a knowing YOU is ego. Ego is comprised of things like labels, status, other outward manifestations of competing with others. Ego is generally considered to be associated with MIND in eastern thought.

If YOU is not the outward self that is presented to others but is the observer of MIND, what/who are YOU?