It's true that the collapse of the Western Roman Empire led to a regression in social order. To blame this complex collapse entirely on Christianity is overly simplistic. There's obviously some casualties during this period of upheaval (like the Palimpsest you mentioned), but if anything the early Christian monasteries deserve some credit for preserving knowledge during this period of tremendous upheaval.
Many have also pointed out how Eurocentric this view is. Mathematics and science continued to flourish in Arabic and Chinese places of learning as well. Algebra, modern astronomy, and the printing press did not pop out of the aether the moment Europeans decided to start printing Greek gods again.