I think there's a third issue, or at least two pieces to your number 2. Whether a government should have the mechanism of banning foods that are safe to eat in

I think there's a third issue, or at least two pieces to your number 2. Whether a government should have the mechanism of banning foods that are safe to eat in moderation available to it is a different question than whether it would be good policy given that mechanism. If the government should be in the habit of regulating nutrition, banning foods with exceptionally poor nutritional qualities is probably good policy, but is that the kind of thing governments should be regulating at all? I would argue that it usually isn't and should only be permitted in exceptional circumstances.