I’m not familiar with Erikson’s work, but I have taken Myer-Briggs and “True Colors.” Like another commenter on this thread, I was amazed at how MB nailed me. True Colors really helped me understand me and people who don’t think like me.

If all these “personality tests” are not rooted in good science, then why are they so popular? Let my offer my perspectives.

1. We, the people outside of any profession, are always looking for a simple explanation for things that are actually quite complicated. We just don’t have the time or intellect to earn a psychology degree. Therefore we gravitate towards these personality tests in a similar way to voting for political parties: simple is better.
2. I’m pretty sure that if I go to three psychologists, I will get three different professional opinions of the state of “Dave Volek.” Which opinion should I follow? Why is one professional psychologist so much better than another?
3. Personality tests provide a common, yet simple, language for the non-professional. This helps us commoner work out a few life conflicts with each other. For example, I am a Green and my wife is a Blue. I have used these differences to help us get along a little better. What’s wrong with that? The alternative is to hire psychologists who will likely speak over our heads and have differing analyses.
4. In my life experience, these personality tests do work somewhat well. At least well enough that we can move forward with our lives.
5. If the personality tests are indeed snake oil, then they wouldn’t have much staying power, would they?