I think he is wrong about their supposed accomplishments in the Middle Ages. There is evidence to show they stole ideas from those they vanquished. Islam has never accomplished anything but murder and plunder.
This won't be received well by Muslims, but one of their accomplishments is converting Jews to Islam by force under threat of death. Hence, the few scientific accomplishments may well have been due to Muslims of Jewish heritage. A tiny Jewish nation of a million or so, annually out-publishes a billion or so Muslims. By a huge factor. Rather than scream and shout in rage, those Muslims should sharpen their logic and contribute to humanity. (Won't happen soon...)