Apparently I need to answer more questions about that before I can even suggest the tag using the SE interface (which is pretty dumb if you ask me.)
Note that simply typing Myers in the tag box (when editing questions) does not search for (i.e. pop up) MBTI. The search apparently doesn't go as deep as using the tag description.
There was one recent questions here that was tagged with pretty much everything every personality-related tag, except the most focused one (which was MBTI). I suspect it's because the acronym doesn't show up in the question, only the spelled-out name does.