I think that's true. Given the way data flows and the location of the data, the U.S. government has the ability to access the data. They're going to continue to access these data regardless of what you do, unless you take rather concrete action to prevent the data being transferred to the U.S. in the first place.
I think this may have more to do with whether Canadians feel a perhaps false sense of reassurance than whether they are actually protected in any way, unfortunately.