People are already not using libraries because they'd rather rot their brains on TikTok than read a book. (Also, for information lookup, the internet and search engines exist, and have for a while now.) This has no actual causal relation.

People is a broad term. Outside of major cities (where I live) libraries serve a very essential service for parents and their children and as a free communal space for the broader community. Our libraries are always full and a large part of the health of our area.