The Hebrew language is a very crude and imprecise language. Talk to scholars who deal daily with both Hebrew and Greek as I have and you will see their frustration at trying to "fill in" the gaps in ordinary Hebrew language manuscripts and second guess what the writers had in mind. To suggest the Hebew language is precise, as compared to Greek doesn't make any sense. That it would suggest (as you say) that Jews came into existence with the brith of Judah is a good example that it is also the source of cultural silliness totally out of touch with real history.
Where did I say the Hebrew language was precise?
I merely said that applying a (relatively modern) English word "Jew" to a certain period of time but not another is silly because the original language makes no such distinction.
No, it's just focused on earthy and tangible content. It looks imprecise if you are needing to make abstract distinctions, which Greek is more suited for.
The correct polarity is not precise/imprecise, but tangible/abstract.