Yes, that would be a perfectly reasonable legislation. The burden would be on the legislators to clearly articulate their viewpoint, and provide reasonable justification for why those materials are inappropriate for any age.
Currently, some of the 850 "suspicious titles" they are "looking into" include books like We Are All Born Free: The Universal Declaration of Human Rights in Pictures [1]. This does not lead me to conclude that their chief concern is safety and curation.
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[1] https://www.npr.org/2021/10/28/1050013664/texas-lawmaker-mat...