Einstein took so long to win a Nobel Prize because the committee saw the theory of relativity as philosophy rather than science. Walter Isaacson's Einstein biography tells the story.
William Ostwald nominated Einstein in 1910. He "cited special relativity, emphasizing that the theory involved fundamental physics and not, as some Einstein detractors argued, mere philosophy." One detractor was the anti-Semite Philipp Lenard, who had an "animosity to the type of 'philosophical conjecturing' that he often dismissed as being a feature of 'Jewish science.'"
This is why Einstein's Nobel Prize was for the photoelectric effect rather than relativity. Svante Arrhenius, presenting the award, said of relativity, "this pertains essentially to epistemology and has therefore been the subject of lively debate in philosophical circles." Arrhenius then continued, "Einstein’s law of the photoelectrical effect has been extremely rigorously tested by the American Millikan and his pupils and passed the test brilliantly."
Philosophers set themselves up to be wrong when they think of themselves on the model of Immanuel Kant, who got the wrong answers to the questions about space and time that Einstein got right. I'm happy to take what the physicists were willing to give us, and call Einstein the greatest philosopher of the 20th century. That would answer the question of whether philosophy makes progress.
