I wish this was not the case.
I do not care who produces the science, we all are one and the same. Science benefits all.
That's what happened during the Mongol Conquests. The fall of Baghdad alone caused at least several hundred thousand people to be killed. The main library, which had collected countless works over the centuries, was gone.
Baghdad was rebuilt, of course. Economically and politically it bounced back since it was still right on the silk road. But scientific study never really recovered there.
[1] Initially listed his brother Batu, rather than Berke, the first Muslim Khan.
And even further west Andalusia was still chugging along. That was definitely an important source of knowledge for the first universities in the rest of Europe.