Once people can write things down, they stop working to make what they learn part of themselves. Memory becomes something kept on the page instead of something carried in the person. In this sense writing can be the enemy of remembrance.
A people who stop obeying a common authority lose the shared defence that kept them safe, and become open to capture and scattering. A collapse like this can feel as permanent as broken china that cannot be mended. People may go on explaining their later troubles as the lasting result of that break.
In this tradition, good and evil are two sides that both must be dealt with rather than one being defeated. Offering sacrifice is the act that brings the two into balance so a person's wishes can come true. Explaining that balance is harder than explaining rituals, texts or ethics.
Peoples without writing can still keep, organise and pass down deep systems of knowledge across generations. A memorised body of verses and stories can grow enormous, with hundreds of thousands of stories in a fixed structure, and still be handed on intact by trained specialists.
Every tree, animal and bird was given its own name and identity when the world was made. Carrying a name also means carrying a responsibility to care for one another. Repairing a damaged world calls for renewing that shared agreement among all living things.