I think philosophy is one of the most misunderstood subjects. That it took so long to become a high school course, I think, attests to this. Even within academia, however, there seems to be confusion.
Two PhDs expressed surprise at the title of my masters’ thesis in Philosophy (“The Issue of Consent in Sex and Sexual Assault”); both seemed to think that philosophy was stuff like ‘If a tree falls and no one’s there, does it make a sound?’ or ‘Does the table really exist?’ Philosophy is that. But not, at all, only that.

Metaphysics (Is the table real?) and epistemology (What’s the difference between believing something and knowing something?) are both areas of philosophy. So are ethics (How could/should we determine right and wrong?) and aesthetics (What do we mean when we say ‘X is beautiful’?).
But so are social philosophy (Why is there war? Are affirmative action programs fair?), political philosophy (Which is better – liberalism or socialism? What is the nature of the just society?), and philosophical psychology or philosophy of mind (What is the relation between the mind and the brain?). And some areas have fields pretty large in themselves: environmental ethics (Should we use animals for experimentation? Do trees have rights?); business ethics (Is profit an acceptable motive? How do we define, exactly, a conflict of interest?); biomedical ethics (Is it right to pay someone for their organ donation? Is euthanasia immoral?).
Truth is, philosophy is not so much a subject as a skill: philosophy is disciplined reflection. So there is, there can be, a ‘philosophy of’ anything or an ‘anything philosophy’: philosophy of science, philosophy of language, philosophy of education, philosophy of love, feminist philosophy, legal philosophy, etc. Whenever you’re examining the conceptual foundations, especially for clarity or consistency, you’re doing philosophy. Far from being the least relevant, philosophy is the most relevant: other disciplines deal with who, what, when, where, and how; philosophy deals mostly with why (after dealing with ‘What exactly do you mean?’).
One of the most misunderstood courses in university is a second year philosophy course called, variously, Critical Thinking, Clear Thinking, or Informal Logic. The template in such courses is ‘I think X because Y’. The purpose of the course is to teach people to have reasons for their opinions – to have good reasons. Most of us know that something can’t be A and not-A at the same time. But there are other rules of reason, rules we constantly break – and this constantly gets us into trouble. (Is your argument sound? Are your premises true? Are they valid – relevant and adequate?) What the course does is teach these rules of reason, the skills of thinking: it develops the capacity to analyze an issue, to break it down into its parts; to draw distinctions, identify assumptions, clarify concepts, understand connections; it trains one to check for coherence, consistency, and completeness. A philosophical analysis is a very careful examination and assessment.
A supervisor once said of me, after I had provided feedback on a sexual harassment brochure, ‘I wish I had a mind like that’. It’s a mind developed by the rigours of philosophy. It’s a mind developed to be clear, to be precise, to be thorough. It’s a disciplined mind. I may not tell you the answers. But by the time a philosopher’s through, you’ll know what all the important questions are (as well as how they’re connected). You’ll also have a pretty good idea of the possible answers, each with their implications.
Whether or not to quit your job, whether or not to have an abortion, whether or not to kill yourself – these are all philosophical questions. Even trying to determine why you feel depressed involves philosophical skills – to uncover and clarify perceptions, assumptions, expectations. In fact, while here in Canada and the U.S. when we advise someone to get counselling or therapy, we mean psychological counselling, there is also such a thing as philosophical counselling. It’s a well developed field in Europe: it has its own journals, its different schools of thought; one can become a certified philosophical counsellor and hang out a shingle for business, much like the familiar psychological counsellor here. As a parallel to psychoanalysis, it makes perfect sense. After all, philosophy is analysis.
Some scientists have attempted to distance themselves - or divorce themselves - from “philosophy” because they believe that the scientific method - particularly as it relates to empiricism - is capable of discovering any truth that is in principle discoverable.
The Great Joke on modern science is that this position is itself pre-rational.
In any case, philosophy is just the word people used before they had the word “science” - and because it’s an old word that has been in use for a long time, it sticks around.
As you point out at the beginning of your article, there are many areas of knowledge that are classified as “philosophy” - metaphysics (my favorite), ethics, politics, etc.
So, my question is, ‘What is the use of a term that is so general in it’s use, as to practically mean anything at all?’
Which is to say, I agree that philosophy means just about any area of knowledge - but what are we to do with a term that is so generally applied? What’s the point of it in the end? Seems like a term you can literally apply to anything a human is capable of learning, or reflecting upon.
I prefer the breakdown of philosophy into more specific domains.
Such as metaphysics, or ethics.
This is chiefly because I love brevity.
You could call these ‘a philosophy of metaphysics’ or a ‘philosophy of ethics’.
Or you could just call it metaphysics and ethics.
Brevity.