Nietzsche and Wittgenstein worked to show many (most) of then current philosophical problems weren't. Bias and language were such a big part of problems that when substracting them, they were rendered hollow. So the subject, as it was until XIX century, could very well be called a problem and yes, it was solved.
Sure, if you totally reframe the entirety of what it means "to solve philosophy" to mean what you said, then gaius's comment makes sense.
I'm not sure I agree that solving a lot of the then/now "problems" with philosophy is the same as solving the entire field of philosophy. Especially since it requires mobile goalposts.