It's true that he, along with Kuhn, are probably the two most influential philosophers of science. But in many respects his philosophy of science is ahistorical--naive falsificationism isn't really present in any of the major scientific revolutions. (One might make the tongue-in-cheek remark that his descriptive theories have been decisively falsified.)

His defenders, of course, would claim that that naive falsificationism is a misreading of him.