As the narrator says, this is not an usual pattern for people to migrate from one thing to next. And if that's the case, then chances are there are many many more people which may end up never finding "that calling". In a way, the above story illustrates the anti "pure hill-climbing" approach: the initial assumption/premise is that you should find a hill and then go really, really far in hopes of making a big contribution. Whereas Ed Witten's story shows that picking one single hill is not necessarily a good idea (local minima!) ... In fact, every once in a while (or systematically), you could jump to a different hill and still come out as a winner. Now the real puzzle is:
a) You could make the argument that your chances of finding the optimal hill for you, on the first try, are very slim. Hence, you should jump at least a few hills.. i.e, your real aptitude lies somewhere else.
b) Jumping too much will/may cause not enough time with anyone subject to make significant contribution - hence it's an optimization problem.
c) The "cross-discipline" question: its often acknowledged that bridging different knowledge areas is very helpful in terms of making interesting discoveries. Does that, in turn, mean that you should jump at least a few hills? If so, how many, and how much time?
Fun questions to ponder... Clearly there is no black and white answer either! Depends on your field, context, etc.