It most certainly CAN be turned off. I specifically turn it off on mine. You can selectively turn off parts of it as well. For example, you can turn off bookmark sync, but leave history sync enabled if you want.
I would say transparency is not the problem as much as a lack of accountability. They keep on doing things like this, and lying to congress and everyone else, but none of them are in jail or even afraid.
I know it is probably outside of the scope of this kind of oath, but I think there should be more work done to encourage publication of results that did NOT show what the researchers/scientists set out to. Negative results are being swept under the rug and ignored. This is a problem that really seems like it should be addressed.