You're leading with the assumption that you and I (or anyone else, really) agrees on what "pornography" is, much less that we agree in a non-partisan context.
The context here is that there's been a significant effort in the last ~18 months to reclassify LGBTQ fiction and non-fiction as pornographic and have it removed from school libraries on that ground. Justifications for that vary, from the more staid pearl-clutching ones, to rehashes of old and dangerous stereotypes about gays predating on children. That is absolutely a doctrinal concern, even if the nominal topic ("don't show children porn") is one that appears reasonable and uncontroversial on face value.