Yeah, I must have totally missed the statuary and paintings the Borg carted off from the people they assimilated.
They assimilated the technology and scientific knowledge. The rest of it was discarded as irrelevant. Did knowledge of a particular species' holidays or religious rituals change one damn thing about how the Borg did things?
Did the Borg themselves create art, form social groups, celebrate holidays, participate in rituals for the purpose of expressing spirituality or fun?
So: What culture did the Borg actually have beyond the same kind of hive-mind mentality that terrestrial social insects have?