They would not talk about this in their public messaging because it would require them to admit that their privacy policies are influenced not just by their own company morals but also by the government.
They would have to say something like "We know some users want to fully encrypt their cloud data. We also want to encrypt their data. But the government won't allow us to do it until we protect their interests in stopping child abuse and terrorism". That would contradict their marketing image of having their interests being aligned with their users'.
They would have to say something like "We know some users want to fully encrypt their cloud data. We also want to encrypt their data. But the government won't allow us to do it until we protect their interests in stopping child abuse and terrorism". That would contradict their marketing image of having their interests being aligned with their users'.