I know the true answer to this, but has there been any reason that any particular locality would want to change this law? IOW, have there been any high profile complaints, or any bad lip service against preemption as it now exists? Perhaps the Norfolk City Council... that's the only one I can think of.
BTW, the new bill in question adds this following text to the bottom of the current Preemption law (emphasis mine):
C. Nothing in this section shall prohibit a locality from adopting an ordinance that prohibits possessing or carrying firearms, ammunition, or components or combination thereof in a community or recreation center, administrative building, or public library owned or operated by the locality during an official meeting of the governing body.