Knowing why it happened doesn't help much right now.
But similar policies are happening right now. Nothing is ever going to change in the NEA, until the members who are disgusted by it seize it away from the political leftist hacks. Until you do, realize that "Barbara Kerr" is the face of your profession, and be prepared to see parents who care walk away from a hopeless situation, leaving you to cope with the uncaring dregs warming seats in your classroom.
IMNSHO, the sooner the union and the LAUSD catastrophically crash and burn, the better. My kids are safely out of the system that was slowly destroying their intellect, curiosity, love of learning, and future. Knowing their future competition is LAUSD educated, their future is brighter by the day.