Why did Jewish scholars in the Middle Ages know little or nothing about Philo Judaeus?

During the Middle Ages, knowledge of Philo Judaeus among Jewish scholars was either very slight or nonexistent. While Philo’s synthesis of Greek philosophy and Jewish doctrine exerted a significant influence on early Christian thought, it did not have a comparable impact on Jewish intellectual circles during the same period.1

It was not until modern times that Philo’s importance in the history of Jewish philosophy was formally recognized. His works, which were written in Greek, were largely preserved and transmitted by the Christian Church rather than through the internal traditions of medieval Jewish scholarship.12