Yes, studying physics is unlike other scientific inquiry — but keep in mind that physics isn’t as cut and dry as it may seem. For example,
General relativity and quantum field theory are incompatible. They both can’t be right…
The other thing, is that you’re comparing the study of two different kinds of systems. Physics is the study of a particular, unchanging system (as far as we know). E.g. the speed of light is constant.
Whereas to study JTBD, is to study evolving systems. For example, life on earth is an evolving system. There are no constants as species come and go. The same is true of the weather. We can make reasonable predictions about the weather because certain dynamics/variables are known — but others are unknown (now that I think about it, perhaps the real issue is incomplete knowledge)
With JTBD we can, and do, engage in experimentation (hypothesis testing). We gather preliminary data about a market, and then make predictions on what product people will choose given a certain set of conditions.
If you haven’t already, I suggest reading The Jobs to be Done Data model. There, I discuss the data we gather/use to come up with a prediction.