@Ego -
It's more than a little annoying that every time people take a strong interest in something around here and a someone disapproves, they start calling it a cult in a insulting fashion. IIRC, Wheaton levels, ERE2, index investors, ... and the forum itself has been called a cult. Never by the people who are into a particular subject---always by those who didn't join the party. If the definition of a cult is used that loosely, even political parties and soccer clubs are cults. Can we not do that? A good rule for respectful behavior is not referring to others in a way that they do not refer to themselves. Also maybe avoid logic like "Von Braun is a rocket scientist. Von Braun is a Nazi. Therefore von Braun can't design a moon rocket." There's a ton of doctors, bankers, coaches, ... with awful personal habits or associations who are otherwise good at their jobs.
Now, that aside ...
OCEAN and MBTI are really different in that the former is not a theory but rather a taxonomy. Now, it could be argued whether that's a feature or a bug. The answer depends on what you intend to use it for and that might be the root of the controversy: Academics vs Practitioners.
OCEAN is a statistical analysis of "experimental results" with no explanatory power. It tells the person where they fall on 5 spectra relative to the rest of the population and people/users are then free to interpret that as they will. An analogue (for one dimension) would be a test that measures where you are on a colorwheel and tells you that you are 57% purple, but then leaves it up to you to explain what purple means. Or having your blood pressure taken and the doctor telling you that your blood pressure is in the 64% percentile while leaving it up to you to figure out what to do with that information. Thanks, doc? This is more difficult and problematic than one might think. For example, many people still don't differentiate between introversion, shyness, and social anxiety, so three people being told that they are 75% introverted could and would interpret that in three different ways. OCEAN will not help with that.
MBTI takes [most of the same OCEAN] data and attempts to explain it using Jung's original 4 cognitive functions. (Most people are probably familiar with Jungian archtypes, but these are not the functions we're talking about.) Eysenck does the same/similar but use another theoretical framework. Theory gets connected to experiment by making sense of the experiment. It goes further by explaining what the data means ... not just what the data is.
MBTI is designed so that it's theoretical structure fits rather well with how some human minds are organized which makes it easy for them to apply it in naturally without constantly looking up what those letters mean. It does require that the user is able to think theoretically; not just follow rules or google results---and this is where many casual testers fail to step up. (This also means that the MBTI structure doesn't fit well with how other minds work. Those who are not proficient in abstract frameworks will struggle with the juggle. Not surprisingly, they also tend to be the ones who complain the most about it ... or any kind of theory.)
Now with some effort using those cognitive functions it becomes possible create descriptions of behavior and preferences that a) people recognize themselves in(*) and b) recognize other's in. (This is more useful/relatable than percentile scores.) This becomes useful when one can go c) from recognition to prediction. In other words, "based on what I've seen, you're much like the typical ABCD, and knowing that you're like ABCD, I can predict a few things about you that I haven't seen".
(*) Some claim the Forer effect that people are likely to recognize themselves in anything. (This is how astrology works.) However, the 16 types are sufficiently different and specific that I challenge anyone making that claim to actually read the 16 different type descriptions first!
I'm well aware that you seek a balanced approach to everything despite any inherent preferences (or in my view, more likely
because of inherent preferences. I bet most of your scores are pretty centered.) Indeed you believe these preferences can be changed with enough practice. This is where I disagree. If I enjoyed doing gymnastics, which is not normal, and my personal fitness test revealed that I was 5 feet tall (assuming I didn't already know, humor me here), I would take that as a validation of my gymnastics preference. If I ignored that information because everybody around me told me that gymnastics sucks and basketball is the only game in town... that might not be good either.
I don't think we disagree on the methods as much as the goals. You seek balance in life (basically proposing that the only sport in town is decathlon). I seek satisfaction.
To clarify, I did not change my stance, but maybe now you see the nuance? If someone has a neurological [brain chemistry] preference for something, they tend to do it and as such they tend to get better at it as practicing anything will do. HOWEVER, if they're made to practice something that their neurochemistry doesn't find rewarding---and this happens all the time with well-intended advice or cultural expectations imposing themselves---they will never be as satisfied with the experience as they could have been. Indeed, they'll likely not be as good as someone whose brain rewards their behavior. As a result, they will be more capable but also less satisfied. Consider why society had to start using conscientiousness-enhancing drugs as every child was sent to get a college education. Consider why so many drink in order to party. They're basically altering their mind in order to make fitting their square peg of a brain into the round hole of a situation more tolerable. So yeah, we can take someone who just doesn't have the mind for conscientiousness and openmindedness (NJ) and send them to school with some adderall... and as a result, we get a kid who can pass an algebra test, but we also get a kid who is unhappier for the experience.
Now, since this is not a cult, people are free to use or misuse the information here as they can and want or don't want. You do not have to use MBTI (or invest with Vanguard
) to join the forum. You don't have to pay money or perform a ritual every time you log on. You're not prevented from believing in other things to stay around. You're not prevented from leaving or required to cut ties with your family. And so on...
Indeed, I think those who are super-into XYZ try to be very helpful in explaining XYZ over and over even though it would be much appreciated if people who are not into XYZ would put in a little more effort than "How come everybody believe in XYZ. I haven't really invested much time in understanding it myself but I heard it's bogus. And look I found a few links on the wiki that confirms it." That just gets old.
And insofar anyone isn't interested in answers from anyone from the supposed cults, they can just ask them to stop---"please stop telling me to invest in index funds"---and they'll do it. On the other hand, demanding that people only answer in a particular way---"please tell me how to invest without mentioning index funds"---is too much to ask. If someone doesn't want an MBTI or WL framed answer from me I'm probably just not going to answer. Live and let live.