People are of different kinds. But it is difficult to prove that. Everybody has something they love to do yet we still could do other things even if they don’t bring much satisfaction and we never will learn to be masters of that domain.
It is possible that personality types will get clearer to determine in the future because humans will have more freedom to choose their own path (as opposed to the historic situation when being from a peasant family you could only be a peasant). Personalities may not be determined entirely by genes but rather by our learning to adapt to the society using own abilities.