If common culture is an effective substrate to communicate ideas as in we can use shared pop culture references to make metaphors to explain complex ideas then the common culture that large companies have ensnared in excessively long copyrights and trademarks to generate massive profits is a useful thing for an LLM that is designed to convey ideas to have embedded in it.

If I'm learning about kinematics maybe it would be more effective to have comparisons to Superman flying faster than a speeding bullet and no amount of dry textbooks and academic papers will make up for the lack of such a comparison.

This is especially relevant when we're talking about science-fiction which has served as the inspiration for many of the leading edge technologies that we use including stuff like LLMs and AI.