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.