This is a bold claim on the glossy brochure of philosophy. I don't see evidence that philosophy has answered any of those questions or has the tools it claims to answer them.

Whenever I hear arguments about the contemporary relevance of philosophy, I ask myself "could these same arguments be applied to Alchemy and Astrology?" These were precursors to modern chemistry and astronomy, and their practitioners made many significant discoveries that we still use today. However, we have updated their methods significantly so though they are still known and read about, but not actively used.

I have not seen solid reasoning and evidence to suggest that philosophy is not in a similar situation.

It was philosophy which set up the standards of 'solid reasoning' and 'evidence' so that we can now distinguish between Chemistry and Alchemy.

It seems that you apply the 'natural sciences' pattern of knowledge generation to philosophy, and conclude that philosophy doesn't produce knowledge. But this stance needs justification. And as soon as you write down arguments that this is the right way to judge philosophy, you are actually doing philosophy yourself.

I see. I think you have never listened a lecture of a good philosopher. I really like Leonard Peikoff. Take for example his lecture called "The American School: Why Johnny Can't Think?" [0]. It has a higher overview than any other science is capable of, reach the essence of the problem and suggest a solution.

[0]: https://www.youtube.com/watch?v=p4BJ-21EhY8

Really? Can you provide an answer for any of these answered by philosophy? On the contrary, it is the sciences that provide answers to these questions, to the extent they are meaningful or the answers are known.

Philosophy is a science. Aristotle answered the essence of theses questions 2400 years ago. He may have commit some mistakes, but the essence is there.

One thing that Aristotle did right was call philosophy "metaphysics". Indeed, philosophy is meta-science.

For the question "How does one acquire knowledge?", I recommend Kant, Hume, Russell, Carnap, and Popper, for a start.

I'd like to ask you how you find out if a question is meaningful? And please don't answer "if it can be answered by science", because then you have a circular argument.