Honestly, I was at a company who got everybody to do the personality tests and then had a marriage counselor sit down with every team to discuss the results. The goal was to help people try to relate to each other more effectively.
It was honestly a decent exercise. I learned that I was one of 3 extroverted programmers at the company (of 150 devs). I don't know that it had much of a lasting impact, but it was solid effort on the part of that company.
The only reason I know the Optimus Prime thing is that they asked us to find a famous figure with a matching personality type to include on our team's internal wiki page.
I think this is right, and a lot of the "this is astrology" people seem to be conflating the fact that something can be useful (which, to be clear, I don't believe astrology is) with the fact that something can be misused.
> I've never seen someone guess horoscope signs above chance.
I've met one person who was David-Blaine-party-trick-level good at this. Out of ~20 people she never met (including me) I think she missed one person's water/earth/fire/air sign, and was probably >80% on guessing their month sign, it was very entertaining.
That's not even getting into how month-of-birth could affect how a child fits into the school system. Some months will be on average older than their classmates, some younger.
I think the second effect is probably stronger in the modern (air-conditioned, artificially-lit, state-schooled) era.
From the abstract: "Winter/spring birth, while associated with an increased risk of schizophrenia, is generally associated with superior outcomes with respect to physical and cognitive development."
Source: Schizophrenia Research 81 (2006) 91–100. "Season of birth is associated with anthropometric and neurocognitive outcomes during infancy and childhood in a general population birth cohort". https://dash.harvard.edu/bitstream/handle/1/3743679/sdarticl...
Also, the questions (at least on last test) thinking/feeling scale seemed to measure values rather then actual personality.
The test might ask such insightful questions as "are you over 65?" and "are both of your parents white?". Then it would use complex algorithms to determine that you are a white retiree.
Where it falls apart is making predictions about how individuals will react to a certain situation or how people will interact with each other. In that I've never seen it do better than just what a socially competent person would accomplish by going with their judgement and intuition, and often worse.
This is a link that describes how people will relate with each other, and I’ve found it to be accurate. Note the type encoding system is slightly different from MBTI, for introverts the last letter has to be flipped.
I want to point out that MBTI is basically a brochure version of an underlying theory. The value comes from understanding the individual cognitive functions themselves. Once you understand that, you can know the _process_ someone uses to think and make decisions. That gives you a better idea of why they think the way they do, especially if their cfs are different / confusing to you. It’s like being able to boot up someone else’s mental… OS in a VM (taxing and slow, but if you really want to run something, necessary.)