It is the job of a board to establish what are the core values staff et al will reference when making core policy decisions. Core values reflect the principles and beliefs that bring volunteers to join a board and support a nonprofit. Over time it is necessary to review core values to reflect changes in the environment and equally important, changes in the composition of the board presuming composition does indeed change in time (which with term limits should be a reality).
Book banning be it public or private reflects the core values of the "owners" of an institution. For nonprofit and public organizations, boards are the surrogate "owners" presumably representing the interests and will of the community or at least constituency served by these institutions. So, as core values shrink or widen, book banning, one indicator of shrinking (in my opinion) of core values, should not come as a surprise. Enlightenment would be what I would pose as the driver of widening such that the parameters of book banning becomes very thin.
And now we turn to today, in the US and of course other countries where limiting rights and responsibilities is that thinning of core values - retro one might say - with consequences that have long term consequences. My point: core values are deep fundamental drivers of what is in the best interest of or reflective of the needs, wants, interests and yes, core values of the constituents. But is this always a reality when the policy makers and deciders as to what will be the core values do not include the constituents in the conversation? I think not.