"But let us never forget, either, as all conventional history of philosophy conspires to make us forget, what the 'great thinkers' really are: proper objects, indeed, of pity, but even more, of horror."
David Stove's "What Is Wrong With Our Thoughts" is a critique of philosophy that I can only call epic.
The astute reader will of course find themselves objecting to Stove's notion that we should be catologuing every possible way to do philosophy wrong. It's not like there's some originally pure mode of thought, being tainted by only a small library of poisons. It's just that there are exponentially more possible crazy thoughts than sane thoughts, c.f. entropy.
But Stove's list of 39 different classic crazinesses applied to the number three is absolute pure epic gold. (Scroll down about halfway through if you want to jump there directly.)
I especially like #8: "There is an integer between two and four, but it is not three, and its true name and nature are not to be revealed."
Fine. My point was that experimental results aren't perfectly transferable either. They require interpretation. Hypotheses are proven and disproven in the context of hundreds of other assumptions. We construct models and theories that we think best explain experimental data. Linguists and economists construct models and theories that best explain observed economic behavior and language use. Linguists and economists, granting some exceptions, agree with each other on lots of issues! There is not as much agreement as there is in physics since there is more room for biases and preconceptions when you can't repeat an experiment over and over again to prove someone wrong. But that doesn't mean linguists and economists aren't getting less and less wrong.
Philosophy is a broad subject. A lot of it (definitely most of it in the English speaking world) isn't just culturally meaningful but scientifically meaningful. In epistemology they try and form models and theories that best explain our understanding of what counts as knowledge. In ethics they do the same for our understanding of what counts as moral. In philosophy of science they try and explain our understanding of what counts as science. There are also fields such as philosophy of physics and philosophy of biology which address philosophical and interpretive issues within those fields like interpreting quantum mechanics (where the philosophers new the Copenhagen interpretation was bunk long before the physicists began realizing it) and the ontological status of biological categories like 'species'. There is Philosophy of Mind, Philosophy of Time, Philosophy of Mathematics etc. That doesn't even include the fields that were once part of philosophy but expanded to become separate subjects (logic, linguistics, cognitive science).There is even something called experimental philosophy where they, you know, experiment. I don't know what your experience with philosophy is. Maybe you just had someone make you read Plato.
Now it is true religions make metaphysical arguments. But I think you're wrong to say it can be used for religion just as well. The metaphysical arguments for God's existence fail. The vast majority of analytic philosophers (and even continental philosophers) are atheists.
But of course there is a whole continental tradition which might be better described as "culturally meaningful" or "politically meaningful". But even here there is an obvious sense in which culturally meaningful philosophy is distinct from fiction. Cultural philosophy makes arguments and descriptions which readers can dispute and challenge. You can say of a cultural philosopher that he does not have a complete grasp of our culture or that his response is misguided. Cultural philosophers hold debates. All the time. Novelists don't. Now, I admit that these debates are not often that valuable since if the two sides have a different understanding of culture they're going to talk past one another. Nonetheless, viewers still have grounds to adjudicate between them and often their thinking inspires political action.
Literature is stories. Stories that may have allegorical or instructional purposes but they're not in a form that one can contradict and that makes them particularly dangerous.