When I first heard about it in grade 8, I thought it was the dumbest thing ever. The first pair, Introvert or Extrovert made sense. But I could never make up my mind on the rest: Intuitive or Sensing, Thinking or Feeling, Judging or Perceiving? I felt I could be either, depending upon mood.
Later I learned that these terms had hyperspecialized meanings, different from how most people use them in everyday speech, especially the latter two pairs (thinking and feeling, judging and perceiving).
Finally I heard that the last pair is some kind of key, which turns the meaning of the middle two pairs. If that does't make sense, that is expected. The letters are just symptoms of inner causes, called the Cognitive Functions, which only the most serious of devotees have heard of, and even fewer understand.
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To go back to basics, it is obvious to me that personality is partly biological. Whether you are introvert or extrovert, for example, doesn't seem to be changeable by sheer force of will or even long, continuous practice. The genetic origin doesn't mean you will match your parents. Just like hair color or the shape of the nose, it can vary, and genes from both sides interact to form a unique child each time. Child 1 can be the polar opposite of Child 2, and things are reinvented once again with Child 3 --- and I don't think it's all explained by birth order. I think there are personality genes.
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The best way I have found to approach Myers Briggs is backwards. Instead of taking a test or trying to understand the exact meaning of each letter, just read the prose descriptions of the 16. https://www.personalitypage.com/html/portraits.html I think you will find some familiar faces in there --- not only a few that sound like yourself but many that remind you of friends. And these are about how you are in default mode, when you are relaxed, not trying. Certainly you can imitate the others for a little while. But some things seem to go with your grain, and others against it. How are you when you behave automatically? That's all that it's about --- not your whole potential when you bring learning and effort into the mix. Some things that are easy and natural for others will always be harder for you, and vice versa.
So there's something to it. My main reservation is that I think 16 is too many, but only by a little. Maybe there are just 12 genetic types (which are further built upon by one's upbringing, experiences, etc., to make each of us unique).
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As a final note, back to the Cognitive Functions, I think they may be hard to grapple with at first, but they are what make Myers Briggs distinctive. It is the only personality theory that posits that how you feel on the inside is often the opposite of how you appear on the outside. For example, I think I am probably an INFJ. Alone in my thoughts or in writing, I am analytical, logical, factual, always trying to come to judgment on this theory or that. But at a party I am open, agreeable (to a fault), even gregarious if my energy is up. Likewise someone else may feel in touch with humanity in their inner selves, but socially will come across as coolly decisive and a hard-nosed debater.