This has always puzzled me. Why does it seem that the vast majority of philosophers love to stray away from plain, clear, specific definitions and step-by-step, verifiable logic? Why is it that people can't be more like Hume or Feynman? Maybe they think that complex ideas can only be explained in a nebulous, vague manner? Every time I read an overgeneralization such as "subject <A> is <x>", especially when the author does not seem to be a scholar in the subject, I cringe. (I'm talking about the obvious need for "guide books". In some cases it's helpful to know the background and such, but many of these books are almost a paragraph by paragraph analysis.)
Actually, a lot of contemporary philosophy -- at least as it is practiced in the English-speaking world -- strives for exactly the "plain, clear, specific definitions" and "verifiable logic" you're looking for. I think the overgeneralizations and nebulous explanations you refer to are more typical of "Continental" philosophy and related disciplines like "critical theory."
The former style of philosophy does produce work that is clearer and easier to read, but it has its own limitations: in the worst cases, philosophers get so hung up on being clear that they shy away from discussing the difficult problems that bring people to philosophy in the first place, and instead spend their careers arguing over minutiae or practicing pseudo-science. Clear definitions aren't going to provide you with the final word on how to treat others, how to organize society, what really exists, or how we know about it.
Then again, the latter style of philosophy doesn't necessarily do much better on addressing these "big questions." Sometimes it is better at keeping these questions in view, but (as you point out) it is often extremely esoteric.
The best philosophers, I think, understand that clear definitions are a starting place, a model that needs to be developed. They see that model as a tool for addressing the thorny, complicated, and tangled questions that philosophers are asked to answer, not as a truth that must be defended in its own right. The goal is to find real philosophical truths. Where a rigorous, methodical approach helps us attain that goal, it should be welcomed; but where that approach becomes a hindrance, it should be left behind.
