The preservation of knowledge, and history, is crucial for the next generations to be able to understand how the world really worked in previous times. It is essential for them to know how their society and world really came to be.
Worryingly, today younger generations are, mostly unknowingly, less and less able to easily access factual documentation of past and present events and developments. Especially by the news media and online people are basically being bombarded with distorted accounts.
When entire generations are not aware of history and its factual accounts then those generations are rendered incapable of harnessing the information that these factual accounts are supposed to preserve and deliver.