I noticed in certain cultures that I interact with here in Malaysia, it seems that the distinction between fact-opinion and objectivity-subjectivity is non-existent. Whereas in STEM and the scientific method, this is a must for practitioners to know - correct me if I'm wrong. So this distinction is predominantly universal or cultural?
Of course people always identify these pair of notions to different degrees, otherwise such a society will be in a mess quickly. From my experience, in western culture one identifies these pair of notions much more strictly than in eastern culture. Western culture emphasizes deductive logic, so one has to identify clearly all the facts from opinions to deduce and support one's argument convincingly. While eastern culture generally emphasizes ones' main inductive thesis/point as a whole. Every culture has its pros and cons, you have to adapt, not complain about...
It is 100% cultural -- something I must concede with great sadness in my heart.
Note that the distinction in question sets rational against irrational. And when it comes to rationality, we, our rational, conscious Self gets shipped as bar-bone hardware of our prefrontal cortex -- and that's it! The hardware part is amazingly powerful, capable of holding and selectively running a comprehensive 3-d simulation of the objective reality -- in one's head! Unfortunately, only the bare minimum of the simulation is hardcoded -- e.g. logic and the rules of inference, discrete time, 3-d space.
As for the rest of it, including the essential knowledge of the world, it has to be acquired separately -- subject to the local laws and regulations. In other words, culturally dependent.